Materials

18 pages, 70867 KB

Open AccessEditor’s ChoiceArticle

Effect of La and Ce Microalloying on the Corrosion Resistance of 0.4Sb Low-Alloy Steel in a Harsh Marine Atmospheric Environment

by Qing Li, Xinyu Wang, Guowei Yang, Da Wei, Junjie Chen, Zhigao Wang, Jun Wang, Xiaojia Yang, Kui Xiao, Xiaogang Li and Zhong Li

Materials 2026, 19(12), 2685; https://doi.org/10.3390/ma19122685 - 22 Jun 2026

Viewed by 356

Abstract

In this study, low-alloy structural steels with different La and Ce contents were prepared via vacuum smelting and controlled rolling and controlled cooling technologies, and their microstructures were characterized. The influence of La and Ce on the corrosion resistance of low-alloy steels was [...] Read more.

In this study, low-alloy structural steels with different La and Ce contents were prepared via vacuum smelting and controlled rolling and controlled cooling technologies, and their microstructures were characterized. The influence of La and Ce on the corrosion resistance of low-alloy steels was compared through indoor cyclic-immersion accelerated tests simulating tropical marine atmospheres. The corrosion mechanism of low-alloy steels with different La and Ce contents in simulated tropical marine atmospheres was investigated using electrochemical measurements and corrosion product analysis. The results show that La and Ce improve the uniform corrosion resistance of low-alloy steels. With increasing La/Ce content, the corrosion current density decreased from 1.8936 × 10⁻⁶ A cm⁻² for 0LaCe to 1.29 × 10⁻⁶ A cm⁻² for 0.3LaCe, corresponding to a reduction of approximately 31.9%. This is attributed to the fact that La/Ce addition promotes rust layer stabilization and densification, as suggested by the evolution of major rust phases and the presence of La/Ce-related oxidized species. Meanwhile, alloying with La and Ce improves the cracking of the rust layer, reduces the number of pores, and stabilizes the rust layer structure. Full article

(This article belongs to the Special Issue Study on Electrochemical Behavior and Corrosion of Materials)

► Show Figures

Graphical abstract

19 pages, 23841 KB

Open AccessArticle

High-Temperature Properties of Magnesium Ammonium Phosphate Cement Modified with Gold Tailings

by Zhenhai Zeng, Peng Yu, Zhuoyi Chen, Jiale Zhou, Haohui Xin, Lie Yu and Anqing Lin

Materials 2026, 19(12), 2684; https://doi.org/10.3390/ma19122684 - 22 Jun 2026

Viewed by 286

Abstract

Magnesium ammonium phosphate cement (MAPC) exhibits rapid setting, high early strength, and potential resistance to elevated temperatures, making it a promising material for rapid repair and fire-resistant applications. Gold tailings (GT), which contain thermally stable Si- and Al-rich components, show potential for improving [...] Read more.

Magnesium ammonium phosphate cement (MAPC) exhibits rapid setting, high early strength, and potential resistance to elevated temperatures, making it a promising material for rapid repair and fire-resistant applications. Gold tailings (GT), which contain thermally stable Si- and Al-rich components, show potential for improving the high-temperature performance of MAPC. However, the mechanisms by which GT affects the residual performance and phase evolution of MAPC after exposure to elevated temperatures remain insufficiently understood. In this study, GT was used to replace the total binder in MAPC mortar at mass replacement levels of 0%, 10%, 20%, and 30%, while the MgO/NH₄H₂PO₄ mass ratio in the remaining binder was kept constant. The effects of GT content on the workability of MAPC mortar, as well as its visual appearance, mechanical properties, mass loss rate, phase evolution, and microstructure after exposure to elevated temperatures, were investigated. The results showed that GT incorporation shortened the setting time and reduced the fluidity and room-temperature strength. After exposure to elevated temperatures, the GT-containing specimens exhibited higher strength retention and lower mass loss rates. After exposure to 1000 °C, the compressive strength of the specimen containing 30% GT reached 15.37 MPa, which was approximately 44.0% higher than that of the specimen without GT. Its flexural strength retention and mass loss rate were 47.42% and 9.84%, respectively. XRD and SEM results indicated that the formation of high-temperature residual phases, including Mg₃(PO₄)₂, Mg₂SiO₄, and aluminosilicates, may contribute to the improvement of the residual matrix structure after exposure to elevated temperatures. Overall, GT incorporation improved the residual mechanical properties of MAPC after exposure to elevated temperatures, and the specimen containing 30% GT showed comparatively superior performance within the experimental scope of this study. These findings provide a reference for the resource utilization of GT in MAPC-based heat-resistant repair materials. Full article

(This article belongs to the Section Construction and Building Materials)

► Show Figures

Figure 1

19 pages, 1552 KB

Open AccessReview

Material-Driven Clinical Complications in Mechanical Circulatory Support: From Blood–Material Interactions to Device-Related Adverse Events

by Klaudia Cholewa, Agnieszka Szuber-Dynia, Jakub Włodarczyk, Klaudia Kurtyka, Artur Kapis, Sachiro Kakinoki, Przemysław Kurtyka, Roman Major and Maciej Gawlikowski

Materials 2026, 19(12), 2683; https://doi.org/10.3390/ma19122683 - 22 Jun 2026

Viewed by 598

Abstract

Mechanical circulatory support (MCS) has transformed the management of advanced heart failure; however, device-related morbidity remains substantially driven by adverse interactions occurring at the blood–material and tissue–device interfaces. Despite progressive miniaturization and the evolution from first-generation pulsatile systems to contemporary continuous-flow devices, thrombotic, [...] Read more.

Mechanical circulatory support (MCS) has transformed the management of advanced heart failure; however, device-related morbidity remains substantially driven by adverse interactions occurring at the blood–material and tissue–device interfaces. Despite progressive miniaturization and the evolution from first-generation pulsatile systems to contemporary continuous-flow devices, thrombotic, hemorrhagic, infectious, and inflammatory complications continue to limit long-term outcomes. This review examines the mechanistic contribution of material properties, surface architecture, and hemodynamic conditions to the pathogenesis of major MCS-associated complications, with particular emphasis on thrombogenicity, biomaterial-induced inflammatory activation, driveline and cannulation-associated infections, hemocompatibility disturbances, and device-related structural failure. The interplay between protein adsorption, platelet activation, complement cascade dysregulation, disturbed shear profiles, and biofilm formation is analyzed as a central determinant of adverse clinical events. Special attention is given to pediatric MCS, in which the continued reliance on extracorporeal pulsatile systems, unique anatomical constraints, and narrow therapeutic margins intensify susceptibility to both thromboembolic and infectious sequelae. Furthermore, the review addresses how material and surface modifications, and emerging biomimetic and anti-thrombogenic coatings may influence complication mitigation. By integrating clinical, engineering, and biomaterials perspectives, this work highlights that many complications traditionally regarded as secondary clinical phenomena are fundamentally rooted in device–material interactions and flow-mediated biological responses. Improved understanding of these mechanisms is essential for optimizing device design, enhancing hemocompatibility, and reducing complication burden in both adult and pediatric MCS populations. Full article

(This article belongs to the Section Biomaterials)

► Show Figures

Figure 1

17 pages, 566 KB

Open AccessSystematic Review

Influence of Final Irrigation on Calcium Silicate-Based Sealer Dentinal Tubular Penetration: A Systematic Review

by Jordi Gómez-González, Daniela Fernández-Negrete, José Luis Sanz, James Ghilotti, Sofía Folguera and Adrián Lozano

Materials 2026, 19(12), 2682; https://doi.org/10.3390/ma19122682 - 22 Jun 2026

Viewed by 321

Abstract

The aim of this systematic review was to assess the influence of different final irrigation protocols and activation methods on the dentinal tubular penetration of calcium silicate-based sealers (CSSs). The review followed the PRISMA 2020 guidelines, and the protocol was registered in the [...] Read more.

The aim of this systematic review was to assess the influence of different final irrigation protocols and activation methods on the dentinal tubular penetration of calcium silicate-based sealers (CSSs). The review followed the PRISMA 2020 guidelines, and the protocol was registered in the Open Science Framework (OSF; DOI: 10.17605/OSF.IO/5HTVN). A PICOS-based research question was formulated, and a comprehensive literature search was conducted in MEDLINE, Scopus, Embase, Web of Science, and SciELO up to October 2025. After study selection, a qualitative synthesis of methodologies and outcomes was performed, and methodological quality was assessed using the QUIN tool. Twenty-one in vitro studies were included, all of which used single-rooted teeth or single roots. The available evidence suggests that final irrigation protocols may influence CSS penetration, although the magnitude and consistency of this effect varied substantially across studies. Sodium hypochlorite (NaOCl) and 17% EDTA were the most frequently investigated irrigants and were generally associated with improved penetration, but no irrigation protocol or activation technique can currently be considered superior. Current research trends include the evaluation of chelating agents, continuous chelation protocols, and irrigant activation systems such as passive ultrasonic irrigation, sonic activation, laser activation, and XP-Endo Finisher. Future studies should standardize irrigation protocols, activation methods, sealer types, obturation techniques, microscopy-based assessment procedures, and penetration outcome measures, while also including larger samples and more anatomically complex root canal systems. Full article

(This article belongs to the Section Biomaterials)

► Show Figures

Figure 1

20 pages, 49534 KB

Open AccessArticle

A Study on the Evolution of Intermetallic Phase Microstructure and High-Temperature Creep Behavior in Mg–8.0Al–1.0Nd–1.5Gd–Mn Alloys

by Jiandong Yang, Wuxiao Wang, Liwen Zhang, Peng Zhou and Tianjun Bian

Materials 2026, 19(12), 2681; https://doi.org/10.3390/ma19122681 - 22 Jun 2026

Cited by 1 | Viewed by 440

Abstract

The effects of Mn/RE (Nd, Gd) multi-modification on the microstructure and high-temperature compressive creep properties of Mg–8.0Al alloys were investigated. The dominant intermetallic phases in the as-cast microstructure are β-Mg₁₇4Al₁₂, Al₂(Gd,Nd), Al₁₁(Gd,Nd)₃, [...] Read more.

The effects of Mn/RE (Nd, Gd) multi-modification on the microstructure and high-temperature compressive creep properties of Mg–8.0Al alloys were investigated. The dominant intermetallic phases in the as-cast microstructure are β-Mg₁₇4Al₁₂, Al₂(Gd,Nd), Al₁₁(Gd,Nd)₃, Al₈(Gd,Nd)Mn₄, and Al₁₀Mn₂(Gd,Nd). The detailed structures of various intermetallics were revealed by TEM; the results indicate that Mn addition promotes grain refinement and facilitates the precipitation of lath-shaped and spherical β-Mg₁₇Al₁₂ in as-cast Mg–Al–RE alloys, resulting in increases in the tensile strength and elongation of the 1.0Mn alloy by 26.5% and 92.1%, respectively. Additionally, thermally stable micron-scale Al₈(Gd,Nd)Mn₄ and Al₁₂(Gd,Nd)₂Mn₅, along with dynamically precipitated spherical nano-sized AlGd and AlNd particles in the α-Mg matrix, were innovatively observed in compression-crept specimens tested at 200 °C and 60 MPa; these phases play a key role in improving high-temperature creep resistance. A significant finding is that excessive Mn addition deteriorates creep performance, which is attributed to excessive grain refinement and the consequent increase in the contribution of grain boundary sliding during creep. However, the negative effect of grain boundary sliding—caused by grain refinement—on creep performance can be balanced by the strengthening effect of Al–Mn–Gd phases and the dynamic precipitation of nanoscale Al–RE particles. This paper provides new insights for designing Mg–Al–Nd–Gd–Mn alloys with both excellent high-temperature creep resistance and significantly enhanced mechanical properties. Full article

(This article belongs to the Section Metals and Alloys)

► Show Figures

Figure 1

14 pages, 3149 KB

Open AccessEditor’s ChoiceArticle

Anisotropic Graphene Oxide Aerogels for Vegetable Oil Absorption

by Daniel Ordóñez Oviedo, Nelly Maria Rosas-Laverde, Arturo Barjola, Enrique Giménez and Alina Iuliana Pruna

Materials 2026, 19(12), 2680; https://doi.org/10.3390/ma19122680 - 22 Jun 2026

Viewed by 327

Abstract

Oil spills represent a critical environmental challenge. The wastewater treatment with porous sorbents presents the advantage of higher uptake and recyclability. In this work, highly porous and low-density three-dimensional reduced graphene oxide aerogels were obtained by hydrothermal reduction followed by lyophilization. The porosity [...] Read more.

Oil spills represent a critical environmental challenge. The wastewater treatment with porous sorbents presents the advantage of higher uptake and recyclability. In this work, highly porous and low-density three-dimensional reduced graphene oxide aerogels were obtained by hydrothermal reduction followed by lyophilization. The porosity and reduction degree of the aerogels were controlled by the addition of reducing species, namely ethylenediamine, and hydrothermal conditions. The aerogels were characterized using scanning electron microscopy, Raman spectroscopy, and energy-dispersive X-ray analysis. The sorption measurements were performed with vegetable oils, namely canola and olive oil, at varying operating temperatures. The morphological analysis revealed a well-defined porosity gradient along the aerogel length, along with a functionalization gradient. The sorption performance is highly dependent on their combined action. The maximum gravimetric absorption capacity was about 122 g g⁻¹ at room temperature, increasing to 156 g g⁻¹ at 60 °C, with the absorption rate increasing from about 1 g g⁻¹ s⁻¹ to 15 g g⁻¹ s⁻¹ within 10 s. These results demonstrate that anisotropic gradient aerogels could be obtained by simple tailoring of the synthesis conditions, and such aerogels could benefit the sorption of oils with higher viscosities in terms of rate, pore filling and retention. Full article

(This article belongs to the Section Carbon Materials)

► Show Figures

Figure 1

22 pages, 4028 KB

Open AccessReview

Control Shear Banding in Metallic Glasses to Enable Tensile Ductility: A Brief Review

by Shan Li, Saisai Zhang, Xiushuo Zhang, Jingli Sun and Haiyang Song

Materials 2026, 19(12), 2679; https://doi.org/10.3390/ma19122679 - 22 Jun 2026

Viewed by 351

Abstract

Metallic glasses (MGs) exhibit excellent mechanical properties, yet their poor tensile ductility greatly limits their practical applications as structural and functional materials. Shear banding is a typical localized rheological deformation behavior inherent to amorphous materials, which stems from heterogeneous atomic rearrangement and regional [...] Read more.

Metallic glasses (MGs) exhibit excellent mechanical properties, yet their poor tensile ductility greatly limits their practical applications as structural and functional materials. Shear banding is a typical localized rheological deformation behavior inherent to amorphous materials, which stems from heterogeneous atomic rearrangement and regional viscosity fluctuations in the glassy matrix, and fundamentally determines the macroscopic mechanical properties of MGs and their composites. This review discusses the relationship between typical toughening strategies and shear banding behavior, and proposes that deliberate suppression of shear band (SB) initiation or deceleration of their rapid propagation can effectively promote distributed plastic flow. In this review, nanosizing and metamaterial strategies are shown to hinder the formation of mature SBs, while metallic glass matrix composites (MGMCs), nanoglasses (NGs), notched design, and rejuvenation treatments contribute to restraining SB propagation. Current approaches have successfully regulated shear banding behavior and thereby realized appreciable tensile ductility in MGs. Novel design and fabrication techniques for amorphous alloys, which suppress SB initiation and retard SB propagation to achieve homogeneous plastic flow, open up new avenues for realizing controllable plasticity of MGs. Full article

(This article belongs to the Special Issue Alloys and Composites: Structural and Functional Applications, Third Edition)

► Show Figures

Figure 1

21 pages, 23905 KB

Open AccessArticle

Span-Morphing Wing Using Multistable Honeycomb Metamaterial Structures

by Ruixin Wang and Bin Niu

Materials 2026, 19(12), 2678; https://doi.org/10.3390/ma19122678 - 22 Jun 2026

Viewed by 380

Abstract

Conventional span-morphing wings are often constrained by structural complexity, heavy weight, and discontinuous aerodynamic surface. Although flexible honeycomb and lattice structures offer lightweight solutions, they usually require external loads to maintain the deformed configuration and often exhibit limited stability under large deformation. In [...] Read more.

Conventional span-morphing wings are often constrained by structural complexity, heavy weight, and discontinuous aerodynamic surface. Although flexible honeycomb and lattice structures offer lightweight solutions, they usually require external loads to maintain the deformed configuration and often exhibit limited stability under large deformation. In this study, a span-morphing wing section based on multistable honeycomb structures is proposed. The multistable honeycomb acts as the core deformation–load-bearing module, enabling multistage reversible spanwise reconfiguration through the bistable transition of cosine curved beams and the support of honeycomb structures. An equivalent nonlinear force–displacement model is derived to describe the structural response. Finite element analysis and fluid–structure interaction analysis are conducted to evaluate its mechanical and aerodynamic performance, while prototype fabrication and bidirectional morphing experiments are performed to demonstrate its functional feasibility. The results show that the proposed wing section achieves prescribed multistage state transitions, effectively regulates lift through span variation, and maintains good structural strength under typical aerodynamic loads. These findings demonstrate the potential of multistable honeycomb structures for lightweight and stable span-morphing wing design. Full article

(This article belongs to the Section Mechanics of Materials)

► Show Figures

Graphical abstract

13 pages, 2461 KB

Open AccessArticle

Atomic-Level Polishing of Single-Crystal Diamond Using a Combination of Reactive Ion Etching and Chemical Mechanical Polishing

by Rongchen Zhang, Xiangbing Wang, Xuejian Cui, Yi Hong, Nan Jiang, Xiangdong Yang and Jian Yi

Materials 2026, 19(12), 2677; https://doi.org/10.3390/ma19122677 - 22 Jun 2026

Viewed by 462

Abstract

Single-crystal diamond (SCD) is an ideal substrate material for semiconductor devices due to its extremely wide bandgap and exceptionally high thermal conductivity. However, diamond’s extreme hardness and chemical inertness pose challenges for the fabrication of ultra-smooth surfaces. Traditional polishing processes are not only [...] Read more.

Single-crystal diamond (SCD) is an ideal substrate material for semiconductor devices due to its extremely wide bandgap and exceptionally high thermal conductivity. However, diamond’s extreme hardness and chemical inertness pose challenges for the fabrication of ultra-smooth surfaces. Traditional polishing processes are not only inefficient but also prone to introducing subsurface defects, which severely degrade device performance. To address the above issues, this study proposes a hybrid polishing process combining reactive ion etching (RIE) surface modification with chemical mechanical polishing (CMP), which enables low-loss atomic-level processing of SCD. The study found that RIE treatment induces lattice disorder on the diamond surface, forming a sp²-hybridized amorphous carbon-modified layer. Compared to the sp³ structure of native diamond, this modified layer has lower hardness and is easier to remove. We conducted the verification of the optimized process using high-quality single-crystalline diamond (SCD) samples with an initial surface roughness Ra of 0.68 nm. Under the optimized RIE parameters (substrate bias power: 200 W, etching time: 600 s, gas flow ratio of Ar:O₂:CF₄ = 40:50:10), the surface roughness Ra was reduced to as low as 0.35 nm after 2 h of CMP treatment. Furthermore, systematic characterization of the SCD’s as-received surface, RIE-modified surface, and CMP-treated surface was performed using Raman spectroscopy and X-ray photoelectron spectroscopy (XPS), elucidating the “etching modification–mechanical removal” polishing mechanism. Full article

(This article belongs to the Special Issue Optical Properties of Crystalline Semiconductors and Nanomaterials)

► Show Figures

Figure 1

38 pages, 1450 KB

Open AccessSystematic Review

Smart Materials Employed in the Construction Industry: A Systematic Review of Types, Properties, Applications, and Sustainability Performance

by Hugo Martínez Ángeles, Cesar Augusto Navarro Rubio, José Gabriel Ríos Moreno, Ivan Gonzalez-Garcia, José Luis Reyes Araiza, Mariano Garduño Aparicio, Ernesto Chavero-Navarrete and Mario Trejo Perea

Materials 2026, 19(12), 2676; https://doi.org/10.3390/ma19122676 - 22 Jun 2026

Cited by 2 | Viewed by 1079

Abstract

The construction sector is undergoing a rapid transition toward more resilient, sustainable, and digitally connected systems, creating increasing demand for materials capable of providing functions beyond conventional structural performance. In this context, smart materials have emerged as promising solutions due to their ability [...] Read more.

The construction sector is undergoing a rapid transition toward more resilient, sustainable, and digitally connected systems, creating increasing demand for materials capable of providing functions beyond conventional structural performance. In this context, smart materials have emerged as promising solutions due to their ability to respond to mechanical, thermal, chemical, or electromagnetic stimuli through adaptive behaviors such as self-healing, structural sensing, energy regulation, vibration control, and reversible deformation. Despite growing scientific interest, available knowledge remains fragmented across specific material families and isolated application domains. Therefore, this study presents a PRISMA-based systematic review of smart materials in construction using peer-reviewed journal literature indexed in Scopus during the 2021–2026 period. The review examines the principal smart material families currently applied in construction, including self-healing concretes, self-sensing cementitious systems, Shape Memory Alloys (SMA), piezoelectric materials, phase change materials, adaptive coatings, conductive nanocomposites, and multifunctional geopolymers. Their engineering functions, structural and architectural applications, reported performance characteristics, sustainability contributions, digital integration potential, and implementation barriers are comparatively discussed and qualitatively synthesized based on the reviewed literature. The findings indicate that smart materials can improve durability, structural health monitoring, seismic resilience, thermal efficiency, lifecycle performance, and carbon reduction when properly integrated into buildings and infrastructure. However, large-scale adoption remains constrained by high initial costs, manufacturing scalability, regulatory uncertainty, long-term durability validation, and limited market confidence. The review further shows that the greatest future potential lies in combining material intelligence with IoT platforms, artificial intelligence, BIM environments, and digital twins. Overall, smart materials are positioned as strategic enablers of next-generation low-carbon, adaptive, and intelligent construction systems. Full article

(This article belongs to the Section Construction and Building Materials)

► Show Figures

Graphical abstract

18 pages, 4240 KB

Open AccessArticle

Packing Densification Response–Constrained Fractal Characterization and Compaction Performance Evaluation of Widely Graded Granular Materials

by Guo-Feng Ren, Xin-Qing Wang, Yi Wang, Qiu-Yue Hu, Xiang-Jun Pei and Xiao-Chao Zhang

Materials 2026, 19(12), 2675; https://doi.org/10.3390/ma19122675 - 22 Jun 2026

Viewed by 410

Abstract

Not all particle-size fractions in widely graded granular materials contribute equally to compaction densification. For non-ideal particle-size distributions (PSDs) with local deviations or fine-end disturbances, the full-range fractal index may be influenced by particle-size fractions that contribute weakly to densification and, therefore, may [...] Read more.

Not all particle-size fractions in widely graded granular materials contribute equally to compaction densification. For non-ideal particle-size distributions (PSDs) with local deviations or fine-end disturbances, the full-range fractal index may be influenced by particle-size fractions that contribute weakly to densification and, therefore, may not consistently represent the maximum dry density response. To address this problem, this study proposes a response-constrained truncation framework to identify a more effective PSD fitting range for fractal characterization. First, 20 concave and S-shaped PSDs from previous experiments were re-analyzed to compare full-range and truncated indices. Then, 21 progressively truncated specimens derived from three standard fractal PSDs were tested by relative density experiments. A unit-mass densification contribution coefficient, η_j, was defined from adjacent maximum dry density differences and particle-fraction mass contents. The η_j-d responses exhibited unimodal patterns, and the transition diameter d_c shifted with PSD coarseness. For the two material sources, replacing the full-range index with the truncated index increased the R² values between the fractal index and maximum dry density from 0.195 to 0.886 and from 0.191 to 0.856, respectively. A continuous percentile search showed that the optimal characteristic scale was concentrated near q ≈ 30, with a robust common optimum of q = 30.53. Sensitivity analysis for β = 0.85–0.95 indicated that 0.225d₃₀ falls within the transition region from highly effective filling to reduced densification efficiency. Accordingly, d_L = 0.225d₃₀ is proposed as a preliminary engineering estimate of the lower fitting limit for non-ideal PSDs. The framework is intended for widely graded materials whose full-range fractal parameters are inconsistent with compaction response. Full article

(This article belongs to the Section Construction and Building Materials)

► Show Figures

Figure 1

26 pages, 4090 KB

Open AccessReview

Research Progress on Preparation Technology, Structure Optimization and Properties of 3D-Printed Porous Ceramics

by Qintao Shen, Peng Wang, Chao Ding, Chunan Song, Yapeng Ning, Renquan Ji, Jiatao Du, Viboon Saetang, Xiaojing Li, Junyi Pan, Yaxuan Wei, Jiying Wang, Xin Yang and Huan Qi

Materials 2026, 19(12), 2674; https://doi.org/10.3390/ma19122674 - 22 Jun 2026

Cited by 2 | Viewed by 692

Abstract

Porous ceramics have garnered widespread attention in high-temperature insulation, aerospace, and other fields due to their excellent thermal stability, low density, and superior thermal insulation performance. However, traditional preparation technologies suffer from limitations such as poor pore structure controllability, unstable mechanical properties, and [...] Read more.

Porous ceramics have garnered widespread attention in high-temperature insulation, aerospace, and other fields due to their excellent thermal stability, low density, and superior thermal insulation performance. However, traditional preparation technologies suffer from limitations such as poor pore structure controllability, unstable mechanical properties, and long production cycles. In recent years, 3D printing (additive manufacturing) technology has emerged as a disruptive approach to address these challenges, enabling precise fabrication of porous ceramics with complex structures and tailored properties. This review comprehensively summarizes the research progress on 3D-printed porous ceramics, focusing on preparation technologies, structure optimization, and performance regulation. First, the principles and drawbacks of traditional preparation methods are analyzed. Then, four mainstream 3D printing technologies (Binder Jetting, Material Extrusion, Vat Photopolymerization, and Material Jetting) for porous ceramics are elaborated on in terms of forming mechanisms, process characteristics, typical cases, and performance advantages/disadvantages. Additionally, the structure–property optimization strategies, including the design of Triply Periodic Minimal Surface structures and the application of computational modeling and simulation, are discussed to achieve the balance between thermal insulation and mechanical properties. Finally, current challenges and future development trends of 3D-printed porous ceramics are prospected. This review provides a systematic reference for the rational selection of preparation technologies, structural design, and performance optimization of porous ceramics, promoting their engineering applications in high-value fields. Full article

(This article belongs to the Section Advanced and Functional Ceramics and Glasses)

► Show Figures

Figure 1

17 pages, 2560 KB

Open AccessArticle

Barrier-Oriented FWGM-Based Fuzzy-FMEA for Risk Assessment and Safety-Barrier Prioritization in Solvent-Based Electrospinning Processes

by Jong Gu Kim and Byong Chol Bai

Materials 2026, 19(12), 2673; https://doi.org/10.3390/ma19122673 - 22 Jun 2026

Viewed by 328

Abstract

This study proposes a barrier-oriented application of conventional failure mode and effects analysis (FMEA) and fuzzy weighted geometric mean (FWGM)-based fuzzy-FMEA for laboratory-scale solvent-based electrospinning. The process was decomposed into 14 sequential steps, and one representative failure mode was defined for each step. [...] Read more.

This study proposes a barrier-oriented application of conventional failure mode and effects analysis (FMEA) and fuzzy weighted geometric mean (FWGM)-based fuzzy-FMEA for laboratory-scale solvent-based electrospinning. The process was decomposed into 14 sequential steps, and one representative failure mode was defined for each step. Severity, occurrence, and detection were rated by a five-member expert panel, and hazard-type-specific weights were assigned to chemical-dominant, electrical-dominant, fire/static-dominant, and combined-dominant hazards. Conventional FMEA identified material review/approval, equipment setup, pre-start inspection, and response to abnormalities as the highest-risk steps (RPN = 60). FWGM-based fuzzy-FMEA re-ranked tied RPN groups and identified response to abnormalities and equipment setup as the joint highest-FRPN failure modes (FRPN = 79.35), followed by pre-start inspection (77.39) and material review/approval (75.89). Barrier-oriented interpretation revealed four dominant mechanisms: upstream information-based hazards, direct high-voltage access, pre-start combined hazards, and intervention under abnormal or residual-energy states. Scenario-based post-control analysis showed that grounded enclosures, interlocks, de-energize-discharge-verify procedures, pre-start checklists, and bonding/grounding measures reduced FRPN by 25.88–43.79% for prioritized failure modes. The proposed framework supports SOP development, equipment improvement, training prioritization, and laboratory risk-assessment documentation for solvent-based nanofiber manufacturing. Full article

► Show Figures

Figure 1

13 pages, 4700 KB

Open AccessArticle

Performance Degradation and Service Life Prediction of Magnesium Oxychloride Cement Recycled Concrete in Western Saline Soil Environment

by Shijie Chai, Nan Wang, Yuze Tian, Wei Gong and Peng Yin

Materials 2026, 19(12), 2672; https://doi.org/10.3390/ma19122672 - 22 Jun 2026

Viewed by 338

Abstract

Western saline soil areas contain a large amount of chloride and sulfate ions, leading to a reduction in the service life of Portland concrete in this environment. Magnesium oxychloride cement recycled concrete (MOCRC) is mainly prepared with light-burnt magnesia and magnesium chloride, which [...] Read more.

Western saline soil areas contain a large amount of chloride and sulfate ions, leading to a reduction in the service life of Portland concrete in this environment. Magnesium oxychloride cement recycled concrete (MOCRC) is mainly prepared with light-burnt magnesia and magnesium chloride, which is more suitable for application in a western saline soil environment than Portland concrete. In this paper, ultrasonic non-destructive testing technology was used to investigate the effects of multiple factors on the deterioration process and service life of MOCRC in a western saline soil environment. The results showed a clear functional relationship between the relative dynamic elastic modulus and the compressive strength or size of MOCRC. On this basis, a multiparameter time-varying degradation model for MOCRC considering the compressive strength, size effect, and environmental error is established. Moreover, a service life prediction model for MOCRC based on the relative dynamic elastic modulus is proposed, using reliability theory and the first-order second-moment method. This study provides a foundational method for the durability examination and service life prediction of MOCRC. Full article

(This article belongs to the Special Issue High-Performance Concrete: Synergies Between Material Innovation and Structural Health Monitoring)

► Show Figures

Figure 1

18 pages, 8919 KB

Open AccessArticle

Effects of Sol–Gel Sealing on Corrosion Behavior for MAO White Thermal Control Coating on MB15 Magnesium Alloy

by Jingying Bai, Chen Wen, Jingkang Zhong, Kuo Zhao, Dongcheng Yang, Zishuo Zhang and Xianhua Chen

Materials 2026, 19(12), 2671; https://doi.org/10.3390/ma19122671 - 22 Jun 2026

Viewed by 487

Abstract

With the aim of achieving outstanding thermal control and corrosion resistance properties, a white MAO thermal control coating sealed by a silicon–zirconium hybrid sol–gel layer was prepared in this work. The corrosion behavior of the coating was evaluated using potentiodynamic polarization and electrochemical [...] Read more.

With the aim of achieving outstanding thermal control and corrosion resistance properties, a white MAO thermal control coating sealed by a silicon–zirconium hybrid sol–gel layer was prepared in this work. The corrosion behavior of the coating was evaluated using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) in 3.5 wt.% NaCl solution. Microstructural and compositional characterizations were conducted using scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy-dispersive spectroscopy (EDS). Results indicated that the sol–gel/MAO composite coating significantly outperformed the single-layer MAO coating in corrosion resistance, primarily due to effective sealing of micro-pores and cracks by the sol–gel layer, which prevented the penetration of corrosive agents. The post-immersion morphological observations were in good agreement with the EIS results. After immersion, the corrosion current density of the composite coating only increased from 10^−6.4 to 10^−5.1 A/cm², while the corrosion potential decreased from −1.25 V to −1.35 V. The post-immersion morphological observations were consistent with EIS results. Meanwhile, the composite coating can effectively mitigate the thermal control performance degradation caused by corrosion. Compared with the MAO coating, the absolute increase in solar absorptance of the sol–gel/MAO coating is reduced by 60%. After 168 h of accelerated corrosion tests in a simulated marine environment, the solar absorptance (α_S) of the sol–gel/MAO coating increased by only 0.05. This study demonstrates that the combination of MAO and sol–gel treatment provides a promising strategy for the development of lightweight, corrosion-resistant magnesium alloys for aerospace applications. Full article

(This article belongs to the Special Issue Corrosion of Materials: Evaluation, Testing, Protection, and Failure Analysis, Third Edition)

► Show Figures

Graphical abstract

20 pages, 10935 KB

Open AccessArticle

Hydration Performance Enhancement Mechanism of Steel Slag-Based Cementitious Materials: Synergistic Regulation of Sodium Silicate and Triethanolamine Complexation

by Li Dai, Feng Chen, Hui Chen, Bin Liu, Minghui Lin, Yi Zhao and Sheng Zeng

Materials 2026, 19(12), 2670; https://doi.org/10.3390/ma19122670 - 22 Jun 2026

Cited by 1 | Viewed by 439

Abstract

This study aims to enhance the hydration performance and mechanical strength of steel slag-based cementitious materials via the synergistic activation of Na₂SiO₃ and triethanolamine (TEA), solving the early-age hydration and low reactivity of steel slag. The mix is 32% steel [...] Read more.

This study aims to enhance the hydration performance and mechanical strength of steel slag-based cementitious materials via the synergistic activation of Na₂SiO₃ and triethanolamine (TEA), solving the early-age hydration and low reactivity of steel slag. The mix is 32% steel slag (SS), 43% blast furnace slag (BFS), 12% desulfurized gypsum (DG), and 13% ordinary Portland cement (OPC). The full factorial design uses Na₂SiO₃ (4–6%) and TEA (0.03–0.08%) as composite activators. Mortar specimens were tested for compressive and flexural strengths at 3d, 7d, 10d, and 28d. XRD, SEM, FTIR, and TG revealed the hydration mechanism and microstructure evolution. The results show an optimal dosage of 5% Na₂SiO₃ and 0.05% TEA increasing compressive strengths at 3d and 28d by 43.10% and 22.09%, respectively, compared with the control group. This synergy improves matrix compactness, supporting the high-value utilization of steel slag and development of steel slag-based cementitious materials. Full article

(This article belongs to the Section Green Materials)

► Show Figures

Figure 1

27 pages, 10100 KB

Open AccessArticle

Experimental Study of Three AlSi10Mg Cellular Structures with Triply Periodic Minimal Surface (TPMS) Topology Subjected to Bending Loading and Identification of Root Aspects of Possible Premature Failure

by Katarina Monkova and Peter Pavol Monka

Materials 2026, 19(12), 2669; https://doi.org/10.3390/ma19122669 - 21 Jun 2026

Viewed by 349

Abstract

The manuscript deals with the bending behavior of beams with relatively less investigated cellular topologies based on triply periodic minimal surfaces (TPMSs). Three types of sandwich-type specimens (namely Schoen IWP, Fischer–Koch S, and Schoen F-RD) with five different volume fractions of 10, 15, [...] Read more.

The manuscript deals with the bending behavior of beams with relatively less investigated cellular topologies based on triply periodic minimal surfaces (TPMSs). Three types of sandwich-type specimens (namely Schoen IWP, Fischer–Koch S, and Schoen F-RD) with five different volume fractions of 10, 15, 20, 25, and 35% (±1%) made of aluminum alloy AlSi10Mg by selective laser melting (SLM) technology were investigated. Three-point bending tests were performed at room temperature on a Zwick/Roell 1456 universal testing machine. The force–deflection dependences were plotted, while in addition to nominal stresses, the effective flexural stiffness and energy absorption to failure were evaluated to compare the properties of the investigated cellular beams. In the preparatory phase, critical aspects of possible premature failure of the samples with the smallest and highest selected volume fractions were addressed, while the manufacturability and fracture surfaces of the samples were assessed in order to improve the input conditions of the setup. By comparing the results obtained in the experimental testing in the second phase, it was found that the highest nominal bending stresses were achieved by the Schoen F-RD structure (although not significantly higher than Fischer–Koch S), but in terms of stiffness and amount of absorbed energy, the Fischer–Koch S structure showed the highest values. The improvement of input parameters led to an increase in the achieved nominal bending stresses by at least 100 MPa for all types of investigated structures compared to the first phase. The combined use of preliminary SLM process optimization, bending tests, and fracture surface/EDX analysis made it possible to relate the flexural response of the investigated TPMS topologies to manufacturing-related defects and premature-failure mechanisms in thin-walled AlSi10Mg cellular structures. The presented specimen configuration is intended as a comparative experimental benchmark for flexural performance of sandwich-type TPMS beams under quasi-static loading. Full article

(This article belongs to the Special Issue Role of Advanced Metallic Materials Within Industry 5.0)

► Show Figures

Graphical abstract

21 pages, 4133 KB

Open AccessArticle

A Cascaded Classification–Regression Framework for Shear Strength Prediction of Cold-Formed Steel Screw Connections

by Shen Liu, Rui Ren, Xiguang Liu and Zheng Luo

Materials 2026, 19(12), 2668; https://doi.org/10.3390/ma19122668 - 21 Jun 2026

Viewed by 468

Abstract

Existing AISI S100 provisions for cold-formed steel (CFS) screw connections lack codified strength equations for screw shear and net section fracture, and traditional machine learning (ML) models struggle to predict these minority failure modes due to imbalanced experimental datasets. This study proposes a [...] Read more.

Existing AISI S100 provisions for cold-formed steel (CFS) screw connections lack codified strength equations for screw shear and net section fracture, and traditional machine learning (ML) models struggle to predict these minority failure modes due to imbalanced experimental datasets. This study proposes a cascaded ML framework that first classifies the failure mode and then predicts strength using mode-specific regressors. Two cascade strategies are evaluated: a Hard Classification Cascade (HC-C) and a novel Probability-Weighted Cascade (PW-C) that weights predictions by class probabilities to mitigate error propagation from misclassification. The predictive performance of the two cascaded models is benchmarked against a single regressor without classification. The superior PW-C model is then compared with AISI S100, and its resistance factor ϕ is subsequently calibrated in accordance with LRFD. Results show that the proposed cascaded models outperform the direct regression model, with PW-C improving the R² for minority-class screw shear from 0.765 to 0.933 and for net section fracture from 0.784 to 0.912. Compared with AISI S100 provisions, PW-C extends coverage to the currently unaddressed failure modes and effectively captures screw group effects on shear strength based on a database of 564 tests. Reliability analysis yields an overall ϕ_c of 0.64 for the PW-C model, with a recommended divisor of 1.15 for direct application within the AISI design framework. This work provides a practical, data-driven pathway for updating design codes to cover failure modes beyond current specification limits. Full article

(This article belongs to the Section Construction and Building Materials)

► Show Figures

Figure 1

17 pages, 12997 KB

Open AccessArticle

Effect of Pore Structure Parameters on Thermal Insulation Performance of Porous Ceramics Fabricated by Material Jetting

by Qintao Shen, Peng Wang, Chunan Song, Chao Ding, Yapeng Ning, Viboon Saetang, Mengji Shen, Yaxuan Wei, Jiying Wang, Renquan Ji, Xin Yang and Huan Qi

Materials 2026, 19(12), 2667; https://doi.org/10.3390/ma19122667 - 21 Jun 2026

Cited by 6 | Viewed by 483

Abstract

Porous ceramics have shown great application potential in aerospace, electronics, and lithium-ion battery thermal management due to their low density, high specific strength, and excellent thermal insulation. Material Jetting (MJ), a high-precision 3D printing technology, enables the fabrication of porous ceramics with tailored [...] Read more.

Porous ceramics have shown great application potential in aerospace, electronics, and lithium-ion battery thermal management due to their low density, high specific strength, and excellent thermal insulation. Material Jetting (MJ), a high-precision 3D printing technology, enables the fabrication of porous ceramics with tailored pore structures, but the synergistic effects of pore structure parameters (configuration, porosity, and number of periods) on their thermal insulation performance remain insufficiently explored. This study systematically investigates the thermal insulation behavior of zirconia porous ceramics fabricated by MJ through experimental tests and numerical simulations. Three typical lattice configurations (Octet, Schwarz, and Gyroid) were selected, and samples with varying porosities (40%, 50%, 60%) and numbers of periods (1, 2, 3) were prepared. The results indicate that the Octet configuration (60% porosity, 3 periods) exhibits the optimal thermal insulation performance, with a minimum cold-end temperature of 58.5 °C (experiment) and 59.21 °C (simulation), attributed to its strut-based structure that forms a more tortuous heat conduction path. For the Gyroid configuration, thermal insulation performance improves with increasing porosity (reducing solid conduction dominance under non-forced convection) and decreases with decreasing number of periods (due to inhomogeneous pore distribution extending heat transfer paths). Notably, the trend of porosity affecting thermal insulation is opposite to that of compressive performance. Numerical simulation results are consistent with experimental data in both values and trends, verifying the reliability of the model. This work clarifies the key factors regulating the thermal insulation of MJ-fabricated porous ceramics and provides practical structural design guidelines for applications such as lithium-ion battery thermal runaway management. Full article

(This article belongs to the Section Advanced and Functional Ceramics and Glasses)

► Show Figures

Figure 1

20 pages, 3929 KB

Open AccessArticle

Multi-Technique Characterization of Historic Blue Bricks from Beijing: Compositional Grouping, Weathering Assessment, and Conservation Implications

by Zhaoyang Zhu, Rui Hu and Bo Zhang

Materials 2026, 19(12), 2666; https://doi.org/10.3390/ma19122666 - 21 Jun 2026

Cited by 1 | Viewed by 391

Abstract

Historic blue bricks are fundamental to Beijing’s architectural heritage, yet cross-site compositional data for guiding material-compatible restoration remain scarce. This study applies WD-XRF, XRD, SEM, thermal expansion measurement, and physical property testing to 21 blue brick specimens from four Beijing-area sites spanning the [...] Read more.

Historic blue bricks are fundamental to Beijing’s architectural heritage, yet cross-site compositional data for guiding material-compatible restoration remain scarce. This study applies WD-XRF, XRD, SEM, thermal expansion measurement, and physical property testing to 21 blue brick specimens from four Beijing-area sites spanning the Tang through Qing dynasties, with PCA and K-means clustering used to explore compositional grouping structures. Within this exploratory dataset, a compositional distinction separates the Ming and Qing Great Wall bricks: CaO falls from 7.7 to 1.5 wt.% as anorthite gives way to albite, while Qing specimens are denser (1.79 vs. 1.65 g·cm⁻³) with lower water absorption (15.9% vs. 20.9%). Two Wanping City bricks are strongly sulfate-enriched (SO₃ up to 9.8%), and WP-SE3 additionally carries a heavy chloride load (Cl 2.1%), masking their original clay signatures and illustrating how unrecognized weathering can distort compositional grouping and source-related interpretation from bulk chemistry. K-means clustering yields compositional types that overlap only partially with site boundaries, capturing raw material variation rather than site-specific manufacturing fingerprints. Despite constraints in sample size and physical property coverage, the integrated dataset offers preliminary compositional benchmarks and limited performance data to inform period-specific brick replacement at these heritage sites. Full article

(This article belongs to the Special Issue Advanced Materials for Heritage and Archaeology (Third Edition))

► Show Figures

Figure 1

21 pages, 17728 KB

Open AccessArticle

Dependence of Tensile Ductility and Impact Toughness on Constituent Particles in 2014 Aluminum Alloy

by Geng Chen, Fang Li, Sijun Chen, Songyi Chen and Kanghua Chen

Materials 2026, 19(12), 2665; https://doi.org/10.3390/ma19122665 - 21 Jun 2026

Viewed by 356

Abstract

In contemporary engineering applications, deficiencies in dynamic mechanical properties, particularly impact toughness, are the leading cause of fracture incidents. Consequently, inadequate dynamic mechanical properties have emerged as the primary constraint limiting the further commercial application of precipitation-strengthened high-strength aluminum (Al) alloys, exemplified by [...] Read more.

In contemporary engineering applications, deficiencies in dynamic mechanical properties, particularly impact toughness, are the leading cause of fracture incidents. Consequently, inadequate dynamic mechanical properties have emerged as the primary constraint limiting the further commercial application of precipitation-strengthened high-strength aluminum (Al) alloys, exemplified by the 2014 aluminum alloy. Since the dynamic mechanical properties of the 2014 wrought aluminum alloy are fundamentally governed by the decohesion and cracking of coarse second-phase constituent particles, it is necessary to quantify the correlation between microstructure and mechanical properties. Meanwhile, the size and volume fraction of constituent particles are largely dictated by the concentration of main and impurity alloying elements. Experimental results revealed that the volume fraction of coarse constituents increased with increasing Cu, Si, and Fe content, and that tensile ductility and impact toughness decreased following an inverse exponential relationship with the volume fraction of constituents. The aim of this study is to establish a quantitative relation to correlate the characteristics of coarse constituents with the tensile ductility and impact toughness of the 2014 aluminum alloy. A mathematical model was developed by regarding the coarse constituents as ellipsoidal inclusions. Their volume fraction and aspect ratio were considered in the model. Model predictions show broad agreement with experimental data. These properties are more sensitive to the volume fraction when it is low. Conversely, a larger aspect ratio leads to higher ductility and toughness. The sensitivity is also greater at a small aspect ratio. The model further indicates that reducing the volume fraction when it is high yields limited improvement, whereas further reduction at a low volume fraction leads to significant enhancement of ductility and toughness. This study correlates coarse constituent characteristics with tensile ductility and impact toughness quantitatively, and provides a theoretical framework for predicting and optimizing the mechanical properties of 2014 aluminum alloy. Full article

(This article belongs to the Section Materials Simulation and Design)

► Show Figures

Graphical abstract

19 pages, 7412 KB

Open AccessArticle

Influence of Mix Composition on the Microstructural Evolution of Leached Cement Pastes

by Kailai Zhang, Wenwei Li, Huamei Yang, Dan Tian, Jinyang Cui, Hao Wang and Fan Li

Materials 2026, 19(12), 2664; https://doi.org/10.3390/ma19122664 - 21 Jun 2026

Cited by 2 | Viewed by 376

Abstract

Calcium leaching increases the hydraulic concrete material’s porosity and the diffusion coefficient, thereby jeopardizing engineering safety. Fly ash and silica fume are commonly used mineral admixtures in hydraulic concrete, and their effects on the material’s leaching characteristics, especially its microstructural and transport properties, [...] Read more.

Calcium leaching increases the hydraulic concrete material’s porosity and the diffusion coefficient, thereby jeopardizing engineering safety. Fly ash and silica fume are commonly used mineral admixtures in hydraulic concrete, and their effects on the material’s leaching characteristics, especially its microstructural and transport properties, require further investigation. In this study, calcium leaching tests were conducted on cement paste (CP), silica fume–cement paste (SF), and fly ash–cement paste (FA) using a 6 mol/L ammonium chloride solution to accelerate the leaching process. Subsequently, a series of quantitative and qualitative analyses was performed on the deteriorated specimens, including phenolphthalein indicator spraying, X-ray diffraction (XRD), nuclear magnetic resonance (NMR), and scanning electron microscopy (SEM). Additionally, the diffusion coefficients of the material at different locations were calculated and analyzed. The results show that partially replacing cement with silica fume or fly ash increases the initial porosity, gel pore content, and initial diffusion coefficients. After 28 days of leaching, compared to the initial values, the porosity increases in the 0–4 mm layer from the leached surface were 83.6% for CP, 11.0% for SF, and 39.0% for FA. The diffusion coefficients increased by factors of 14.3 (CP), 6.1 (SF), and 13.6 (FA), indicating enhanced resistance to leaching. The primary reason for this is that the reactive silica in the admixtures undergoes a pozzolanic reaction with the calcium hydroxide generated by cement hydration, producing additional calcium silicate hydrate (C-S-H) gel, which reduces the capillary pores that would otherwise result from calcium hydroxide decomposition. Full article

(This article belongs to the Special Issue Sustainable Construction and Building Materials: Microstructure, Mechanical Performance, and Long-Term Durability)

► Show Figures

Figure 1

10 pages, 3407 KB

Open AccessCommunication

Phase Engineering of TiO₂/MXene Heterostructure Nanosheets for Enhanced Photocatalysis

by Yuntao Huang, Zibo Chen, Zhenyu Gong, Zhihong Dai, Cheng Chen and Daping He

Materials 2026, 19(12), 2663; https://doi.org/10.3390/ma19122663 - 20 Jun 2026

Viewed by 367

Abstract

TiO₂-based heterostructures have attracted considerable attention in photocatalytic pollutant degradation owing to their enhanced photoresponse and improved charge separation. The phase structure of TiO₂ strongly affects its band structure and interfacial charge-transfer behavior, making phase structure control critical for optimizing [...] Read more.

TiO₂-based heterostructures have attracted considerable attention in photocatalytic pollutant degradation owing to their enhanced photoresponse and improved charge separation. The phase structure of TiO₂ strongly affects its band structure and interfacial charge-transfer behavior, making phase structure control critical for optimizing photocatalytic performance. However, due to the small difference in free energy among TiO₂ phase structure and the strong dependence of TiO₂ nucleation and growth on the local reaction environment, it remains challenging to precisely control the phase structure of TiO₂ in the TiO₂-based heterostructure nanomaterials. Herein, we achieved the phase engineering of TiO₂/MXene heterostructure nanomaterials through a solvent-regulation strategy. Specifically, by regulating the acetonitrile/water ratio in the hydrothermal solvent, TiO₂ with distinct phase structures was in situ grown on hydrothermally treated MXene nanosheets, resulting in two representative TiO₂/MXene heterostructure nanosheets: anatase TiO₂/MXene and rutile TiO₂/MXene. Acetonitrile likely acted as a surface-adsorbing agent during TiO₂ formation, stabilizing the anatase phase and promoting the preferential formation of anatase TiO₂. Benefiting from the optimized heterostructure, TiO₂/MXene heterostructure nanosheets promoted the generation of singlet oxygen (¹O₂), leading to enhanced photocatalytic degradation. Full article

(This article belongs to the Topic Advanced Materials in Chemical Engineering)

► Show Figures

Graphical abstract

27 pages, 11202 KB

Open AccessArticle

Simulation and Experimental Study on Parameter Optimization for the Glass Molding Process of Automotive Panoramic Roofs

by Ruili Wang, Hongyan Wang, Na Xiao, Zihao Hu, Wenjun Tong, Xiaohong Yang and Wuyi Ming

Materials 2026, 19(12), 2662; https://doi.org/10.3390/ma19122662 - 20 Jun 2026

Viewed by 502

Abstract

The automotive panoramic roof exhibits a large-size and thin-wall geometry, with a length-to-thickness ratio approaching the thousand level. This geometric feature makes its forming quality highly sensitive to forming conditions. During the glass molding process, variations in temperature evolution, loading, and cooling parameters [...] Read more.

The automotive panoramic roof exhibits a large-size and thin-wall geometry, with a length-to-thickness ratio approaching the thousand level. This geometric feature makes its forming quality highly sensitive to forming conditions. During the glass molding process, variations in temperature evolution, loading, and cooling parameters may lead to residual stress accumulation and springback deformation, thereby affecting dimensional accuracy and final forming quality. In this study, a full-process finite element model was established and combined with an L16(4^5) orthogonal design to investigate the effects of five key process parameters—heating temperature, holding time, quenching air velocity, quenching air pressure, and quenching time—on the mean residual stress and mean springback displacement in the glass molding process (GMP). The results showed that, within the given parameter ranges, heating temperature, holding time, and quenching time had relatively pronounced effects on the mean residual stress; the mean residual stress was relatively low when the heating temperature was 680 °C, the holding time was 3 s, and the quenching time was 12 s. Heating temperature, quenching air velocity, and quenching time had relatively pronounced effects on the mean springback displacement; the mean springback displacement was relatively low when the heating temperature was 677.5 °C, the quenching air velocity was 13 m/s, and the quenching time was 10 s. Based on the orthogonal analysis, regression models for the mean residual stress and mean springback displacement were further developed, and parameter combinations were screened using the NSGA-III method. Experimental validation showed that the relative error of the mean residual stress was controlled within 15%, indicating that the established model could, to some extent, capture the relationship between process parameters and forming quality indicators, thereby providing guidance for precision forming and process optimization of large-scale thin-walled automotive panoramic roofs. Full article

(This article belongs to the Section Advanced and Functional Ceramics and Glasses)

► Show Figures

Graphical abstract

18 pages, 8437 KB

Open AccessArticle

A First-Principles Study of Formaldehyde Adsorption on the Surface of ZnO

[20 \bar{2} 1]

High Index Polar Facet

by Chao Ma, Jingze Yao, Xuefeng Xiao, Yujie He and Hao Zhang

Materials 2026, 19(12), 2661; https://doi.org/10.3390/ma19122661 - 20 Jun 2026

Viewed by 483

Abstract

High-sensitivity detection of formaldehyde is critically important for environmental protection and public health. Zinc oxide (ZnO) is a widely used core material for chemiresistive gas sensors; however, its conventional low-index facets suffer from a limited number of active sites, creating a bottleneck for [...] Read more.

High-sensitivity detection of formaldehyde is critically important for environmental protection and public health. Zinc oxide (ZnO) is a widely used core material for chemiresistive gas sensors; however, its conventional low-index facets suffer from a limited number of active sites, creating a bottleneck for further sensitivity enhancement. To overcome this limitation, this study pioneers the application of the highly reactive ZnO

[20 \bar{2} 1]

high-index polar surface for formaldehyde detection. By leveraging its unique stepped atomic configuration and unprecedented density of coordination-unsaturated active sites, we systematically investigate the formaldehyde adsorption behavior and the underlying sensing mechanism using first-principles calculations based on density functional theory (DFT). The pristine ZnO

[20 \bar{2} 1]

surface exhibits intrinsic metallic character. At a coverage of 1 monolayer (ML), the most stable G1 configuration achieves an adsorption energy of −1.54 eV per CH₂O molecule. Within a 2 × 1 supercell, formaldehyde adopts both associative and dissociative adsorption modes. At a lower coverage, formaldehyde forms a stable bidentate structure through dual C–O and Zn–O bonding interactions. Electronic structure analysis reveals significant orbital hybridization and interfacial charge redistribution upon adsorption. Notably, associative adsorption opens a bandgap of 0.04 eV at the Fermi level, inducing a metal-to-semiconductor transition. In contrast, dissociative adsorption results in pronounced n-type doping, thereby elucidating the microscopic origin of the resistivity decrease observed in ZnO-based sensors. Overall, this work highlights the structural advantages of high-index facets and demonstrates for the first time the superior formaldehyde adsorption capability of the ZnO

[20 \bar{2} 1]

facet, providing robust theoretical guidance for the rational design of next-generation, high-performance gas-sensing materials. Full article

(This article belongs to the Section Materials Simulation and Design)

► Show Figures

Graphical abstract

22 pages, 13504 KB

Open AccessArticle

Optimization of Mixture Parameters for Rubber-Modified Permeable Concrete Bricks Using Response Surface Methodology

by Jiaxiong Zhan, Wei Qiao, Yiran Qin, Zhihua Luo, Haoxian Shi and Jing Li

Materials 2026, 19(12), 2660; https://doi.org/10.3390/ma19122660 - 20 Jun 2026

Viewed by 412

Abstract

Permeable concrete bricks incorporating waste tire rubber particles were prepared to improve sustainability and optimize the balance between mechanical performance and hydraulic behavior. Orthogonal experiments and response surface methodology were used to investigate the effects of aggregate-to-binder ratio (A/B), water-to-binder ratio (W/B), rubber [...] Read more.

Permeable concrete bricks incorporating waste tire rubber particles were prepared to improve sustainability and optimize the balance between mechanical performance and hydraulic behavior. Orthogonal experiments and response surface methodology were used to investigate the effects of aggregate-to-binder ratio (A/B), water-to-binder ratio (W/B), rubber content, and rubber particle size on compressive strength and permeability coefficient. Results showed that rubber content dominated compressive strength, while A/B ratio had the greatest influence on permeability. Compressive strength decreased continuously with increasing rubber content and A/B ratio, whereas permeability increased with A/B ratio and showed non-monotonic responses to rubber content and particle size. Response surface optimization identified an optimum mixture: A/B = 3.006, W/B = 0.45, rubber content = 0.103, and rubber particle size = 0.525 mm, yielding a compressive strength of 18.97 MPa and a permeability coefficient of 1.82 mm/s. Validation tests showed relative errors of 1.32% for compressive strength and 3.85% for the permeability coefficient, respectively. SEM and CT analyses revealed that the performance of the permeable concrete bricks was governed by the balance among skeleton integrity, interfacial bonding, and pore connectivity. These findings support the valorization of waste tire rubber in sustainable permeable paving materials. Full article

(This article belongs to the Section Construction and Building Materials)

► Show Figures

Figure 1

16 pages, 3750 KB

Open AccessArticle

Dynamic Magnetostatic Energy Correction Based on Domain Area Evolution for Mesoscopic Hysteresis Modeling

by Mengxing Li, Yao Ying, Jing Yu, Jingwu Zheng, Juan Li, Liang Qiao, Akihisa Inoue and Shenglei Che

Materials 2026, 19(12), 2659; https://doi.org/10.3390/ma19122659 - 20 Jun 2026

Viewed by 302

Abstract

In mesoscopic domain energy models of electrical steel sheets, the demagnetizing field H_d is usually held constant at its domain-wall-complete value throughout magnetization. This treatment overestimates the magnetostatic energy at intermediate states and distorts the simulated hysteresis loop. We introduce a field-dependent [...] Read more.

In mesoscopic domain energy models of electrical steel sheets, the demagnetizing field H_d is usually held constant at its domain-wall-complete value throughout magnetization. This treatment overestimates the magnetostatic energy at intermediate states and distorts the simulated hysteresis loop. We introduce a field-dependent coefficient υ_H that scales the magnetostatic energy at each field step. The coefficient is calculated from the aligned-domain area measured by magneto-optical Kerr microscopy and is anchored at the negative coercivity point H = −H_c, where the macroscopic magnetization vanishes and the aligned-domain area S₀ is minimal. The definition follows from the linear relation H_d ≈ N_d·M that holds during domain-wall motion. Measurements in two observation zones of a grain-oriented steel give consistent υ_H curves, confirming the repeatability of the method. When the correction is incorporated into an Assembly Domain Structure Model, the coercivity error drops from 113% to 9–22% relative to the experimental average, with the predicted value falling inside the experimental range, and the remanence error drops from 39.9% to 15–17%. The same correction, applied to a second grain-oriented steel of a different grade, likewise reduces the coercivity and remanence errors (to about 23% and 18%, respectively), confirming that the method is applicable across grades. Full article

(This article belongs to the Special Issue Advances in Characterization, Modeling and Design of Magnetic Materials)

► Show Figures

Figure 1

28 pages, 7007 KB

Open AccessArticle

Stability Prediction of Multi-Factor Coupled Cast Iron Milling System Based on an Improved Full-Discretization Method

by Han Zhang, Minghui Li and Yan Xia

Materials 2026, 19(12), 2658; https://doi.org/10.3390/ma19122658 - 20 Jun 2026

Viewed by 277

Abstract

Cast iron components are indispensable in aerospace and automotive systems, yet their milling operations are severely affected by regenerative chatter, which degrades machining quality and damages equipment. Although various chatter prediction methods have been reported, the optimal interpolation strategy of full-discretization methods (FDMs) [...] Read more.

Cast iron components are indispensable in aerospace and automotive systems, yet their milling operations are severely affected by regenerative chatter, which degrades machining quality and damages equipment. Although various chatter prediction methods have been reported, the optimal interpolation strategy of full-discretization methods (FDMs) for multi-factor coupled dynamic systems remains unclear. This study proposes an enhanced FDM to fill this research gap. A dynamic milling model accounting for regenerative effects, modal coupling and process damping is established, and an improved FDM based on Lagrange interpolation is further developed. A systematic single-factor analysis is carried out to examine the performance of 1st–4th-order interpolation for state, delay and periodic terms. Counter-intuitively, convergence analysis and stability lobe diagram (SLD) verification reveal that higher-order interpolation does not guarantee better performance. The optimal orders are identified as 2nd/3rd for state terms, 3rd for delay terms and 1st for periodic terms. Accordingly, the proposed 321-FDM (3rd-order state, 2nd-order delay, 1st-order periodic) exhibits higher accuracy and computational efficiency compared with benchmark methods, namely the semi-discretization method and Hermite-based 3rd-order FDM. Milling experiments on cast iron workpieces validate the established model and the 321-FDM, and the experimental stability thresholds agree well with numerical predictions. This work presents a validated, high-performance stability prediction tool for chatter avoidance in cast iron machining. Full article

(This article belongs to the Section Manufacturing Processes and Systems)

► Show Figures

Figure 1

14 pages, 1595 KB

Open AccessFeature PaperArticle

Depth of Cure of a Simplified Bulk-Fill Universal Composite and a Conventional Resin-Based Composite

by Alexis Maquère, Darien DeWolf, Daniel Labrie and Richard B. Price

Materials 2026, 19(12), 2657; https://doi.org/10.3390/ma19122657 - 20 Jun 2026

Viewed by 419

Abstract

Objectives: This study evaluated the influence of shade, irradiance, and exposure time on the depth of cure (DoC) of a simplified bulk-fill universal composite (Tetric plus Fill) and a conventional composite (Filtek Supreme Ultra). Methods: The 80% bottom-to-top hardness ratio was used as [...] Read more.

Objectives: This study evaluated the influence of shade, irradiance, and exposure time on the depth of cure (DoC) of a simplified bulk-fill universal composite (Tetric plus Fill) and a conventional composite (Filtek Supreme Ultra). Methods: The 80% bottom-to-top hardness ratio was used as an empirical cutoff, and 99% confidence intervals were calculated using R version 4.5.1. Results: The DoC values were material and protocol dependent. Tetric plus Fill reached the 80% threshold to depths ranging from 3.5 to 4.5 mm, depending on shade and exposure protocol. All the Tetric plus Fill and the Filtek Supreme Ultra products reached their manufacturer’s claimed DoC depth with both 3 s extra-high and 10 s high exposures from the Bluephase PowerCure. Significance: This study highlights the importance of following the manufacturers’ recommendations for increment thickness and exposure time and of recognizing that shade and material formulation influence DoC. Full article

(This article belongs to the Special Issue Recent Research in Restorative Dental Materials (2nd Edition))

► Show Figures

Graphical abstract

43 pages, 5388 KB

Open AccessArticle

Influence of Polarization Temperature and Time on the Electromechanical Performance of Commercial PZT-4 Ceramics

by Bruna Karina da Silva Oliveira, Douglas Santos Silva, Raí Felipe Pereira Junio, João Gabriel Passos Rodrigues, Rubens Lincoln Santana Blazutti Marçal, Sergio Neves Monteiro, Priscila Simões Teixeira Amaral, Roberto da Costa Lima and Foluke Salgado de Assis

Materials 2026, 19(12), 2656; https://doi.org/10.3390/ma19122656 - 20 Jun 2026

Viewed by 397

Abstract

Commercial lead zirconate titanate (PZT) ceramics are widely employed in electromechanical devices due to their excellent piezoelectric response and operational stability. This study investigates the influence of polarization temperature and time on the electromechanical performance of commercial Sparkler PZT-4 (Navy Type I) ceramics. [...] Read more.

Commercial lead zirconate titanate (PZT) ceramics are widely employed in electromechanical devices due to their excellent piezoelectric response and operational stability. This study investigates the influence of polarization temperature and time on the electromechanical performance of commercial Sparkler PZT-4 (Navy Type I) ceramics. Samples were compacted, sintered at 1230 °C, and polarized under temperatures ranging from 80 to 110 °C for 2, 8, and 15 min using a constant electric field of 3.0 kV/mm. Microstructural, physical, and crystallographic analyses confirmed the successful processing of the ceramics, yielding an apparent density of 7.68 g/cm³, relative density of 96.02%, and the predominance of the tetragonal Pb(Zr,Ti)O₃ perovskite phase. Electromechanical characterization revealed a strong dependence of the piezoelectric coefficient (d₃₃) and electromechanical coupling factor (K_p) on the polarization conditions. Maximum values of d₃₃ = 325.8 pC/N and K_p = 0.509 were obtained under elevated temperatures and longer polarization times. A phenomenological Avrami approach indicated faster apparent domain alignment at higher temperatures, while ANOVA and Tukey tests confirmed the significant influence of polarization parameters on the electromechanical response. The results identify favorable polarization conditions for commercial PZT-4 ceramics used in sensors, actuators, and ultrasonic transducers. Full article

(This article belongs to the Section Advanced and Functional Ceramics and Glasses)

► Show Figures

Graphical abstract

Journal Menu

Journal Browser

Materials, Volume 19, Issue 12 (June-2 2026) – 256 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI