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Nanomaterials
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Design and Applications of Heterogeneous Nanostructured Materials
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Design and Applications of Heterogeneous Nanostructured Materials

A special issue of Nanomaterials (ISSN 2079-4991). This special issue belongs to the section "Synthesis, Interfaces and Nanostructures".

Deadline for manuscript submissions: closed (20 February 2025) | Viewed by 9380

Special Issue Editors

Prof. Dr. Hongbo Ju

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Guest Editor
School of Materials Science and Engineering, Jiangsu University of Science and Technology, Mengxi Road 2#, Zhenjiang 212003, China
Interests: PVD; hard coatings; tribological properties; 3D
Special Issues, Collections and Topics in MDPI journals
Dr. Bingyang Ma

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Guest Editor
School of Materials Science and Engineering, Shanghai Dianji University, Shanghai 201306, China
Interests: coatings; PVD sputtering; mechanical and tribological performances
Special Issues, Collections and Topics in MDPI journals
Dr. Manuel António Peralta Evaristo

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Guest Editor
Department of Mechanical Engineering, University of Coimbra, Coimbra, Portugal
Interests: surface modification of surfaces by Physical Vapor Deposition (PVD); development of coatings for mechanical applications to decrease wear and friction; study the tribological processes associated low wear and friction
Dr. Jicheng Ding

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Guest Editor
School of Materials Science and Engineering, Anhui University of Technology, Maanshan 243002, China
Interests: PVD hard coating technology; carbon-based film
Dr. Filipe Fernandes

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Guest Editor
CIDEM, ISEP—Polytechnic of Porto, Rua Dr. António Bernardino de Almeida, 4249-015 Porto, Portugal
Interests: hard coatings; machining; materials characterization; corrosion
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Inspired by nature, heterogeneous nanostructured materials, composed of heterogeneous zones with dramatically different mechanical or physical properties, have rapidly come to represent an important research field. Compared to homogeneous materials, heterogeneous nanostructured materials exhibit superior functional and mechanical properties, which is why they have evolved through natural selection and are often explored by humans. The design, synthesis, and applications of such materials represent important research directions.

This Special Issue of Nanomaterials, “Design and Applications of Heterogeneous Nanostructured Materials”, will include original research and critical review articles on recent advances in aspects of heterogeneous nanostructured materials for use in a range of systems and their applications. The scope includes, but is not limited to, the following topics:

  • Fundamental and new concepts in surface technologies;
  • Hard coatings for cutting tools;
  • Self-lubricant coatings for critical applications for reducing wear and/or friction;
  • Advanced characterization techniques for hard coatings;
  • Advanced 3D materials;
  • Simulations of the microstructure and performance of hard coatings.

Dr. Hongbo Ju
Dr. Bingyang Ma
Dr. Manuel António Peralta Evaristo
Dr. Jicheng Ding
Dr. Filipe Fernandes
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Nanomaterials is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • nano-strcutured materials
  • surface engineering
  • 3D-printed materials
  • self-lubricant coatings
  • simulations

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  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
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  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue policies can be found here.

Published Papers (11 papers)

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Research

17 pages, 49882 KiB  
Article
High-Temperature Oxidation and Wear Resistance of TiAlSiN/AlCrN Multilayer Coatings Prepared by Multi-Arc Ion Plating
by Jie Liu, Haijuan Mei, Junfang Hua, Juan Wang, Yongchao Wang, Genmiao Yi and Xin Deng
Nanomaterials 2025, 15(7), 503; https://doi.org/10.3390/nano15070503 - 27 Mar 2025
Viewed by 302
Abstract
TiAlSiN and AlCrN coatings are two representative coatings with excellent properties in TiN-based and CrN-based coatings, respectively. Multilayering is one of the most important directions for coating performance optimization. In this paper, nanoscale monolayer TiAlSiN, AlCrN, and multilayer TiAlSiN/AlCrN coatings were prepared. The [...] Read more.
TiAlSiN and AlCrN coatings are two representative coatings with excellent properties in TiN-based and CrN-based coatings, respectively. Multilayering is one of the most important directions for coating performance optimization. In this paper, nanoscale monolayer TiAlSiN, AlCrN, and multilayer TiAlSiN/AlCrN coatings were prepared. The microstructure, mechanical properties, oxidation resistance, and wear resistance of the above three coatings were investigated. The following properties of the TiAlSiN/AlCrN coating, including phase, nanohardness, elastic modulus, adhesion strength, and oxidation resistance, fall between those of the TiAlSiN and AlCrN coatings and conform to the “law of mixtures”. Due to the interfacial effect of the multilayer coating, the residual stress of the TiAlSiN/AlCrN coating is less than that of the two monolayer coatings. At 500 °C, the order of wear resistance of the three coatings is consistent with the order of H3/E*2 values, i.e., TiAlSiN > TiAlSiN/AlCrN > AlCrN; at 800 °C, the order of wear resistance becomes TiAlSiN/AlCrN > TiAlSiN > AlCrN because TiAlSiN coating has entered the rapid oxidization stage first, reducing its wear resistance. Full article
(This article belongs to the Special Issue Design and Applications of Heterogeneous Nanostructured Materials)
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10 pages, 6041 KiB  
Article
Investigating the Effects of Long-Term Ambient Air Storage on the Sliding Properties of N-Alloyed MoSe2 Coatings
by Talha Bin Yaqub, Irfan Nadeem, Muhammad Aneeq Haq, Muhammad Yasir, Albano Cavaleiro and Mitjan Kalin
Nanomaterials 2025, 15(6), 414; https://doi.org/10.3390/nano15060414 - 7 Mar 2025
Viewed by 463
Abstract
Transition metal dichalcogenide coatings have emerged as potential candidates for terrestrial and aerospace mobility applications. Among these, the alloyed MoSe2 coatings have displayed promising results while sliding in diverse environments. N-alloyed Mose2 coatings provide the additional benefit of overcoming the impact [...] Read more.
Transition metal dichalcogenide coatings have emerged as potential candidates for terrestrial and aerospace mobility applications. Among these, the alloyed MoSe2 coatings have displayed promising results while sliding in diverse environments. N-alloyed Mose2 coatings provide the additional benefit of overcoming the impact of PVD compositional variations on dry sliding, making them promising solid lubricants for mobility-sector applications. However, the impact of long-term storage has never been investigated for this rarely studied solid-lubricant system. This study investigates the tribological performance of direct current magnetron sputtered MoSeN coatings after 40 months of storage in an ambient atmosphere. Sliding tests were conducted under conditions consistent with pre-storage conditions. The results showed that coatings with 0 at. %, 22 at. %, 33 at. %, and 35 at. % N-alloying exhibited COF values nearly identical to the pre-storage results, with only a negligible increase in ~0.01. Similarly, all coatings displayed specific wear rates in the range of 10−7, aligning with earlier findings. The obtained results show that the sliding performance of MoSeN coatings does not deteriorate over time, highlighting their suitability for critical aerospace applications, where components and assembled parts may be stored for years before launching into space or in actual applications. Full article
(This article belongs to the Special Issue Design and Applications of Heterogeneous Nanostructured Materials)
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18 pages, 13259 KiB  
Article
Impact of Ni Doping on the Microstructure and Mechanical Properties of TiB2 Films
by Ying Wang, Xu Wang, Hailong Shang, Xiaotong Liu, Yu Qi, Xiaoben Qi and Ning Zhong
Nanomaterials 2025, 15(3), 229; https://doi.org/10.3390/nano15030229 - 31 Jan 2025
Viewed by 732
Abstract
The TiB2 film exhibits exceptional hardness and chemical stability due to its unique crystal structure and robust covalent bonds, but it also demonstrates high brittleness and poor toughness, which restricts its practical applications in engineering. By appropriately incorporating metal dopants, the toughness [...] Read more.
The TiB2 film exhibits exceptional hardness and chemical stability due to its unique crystal structure and robust covalent bonds, but it also demonstrates high brittleness and poor toughness, which restricts its practical applications in engineering. By appropriately incorporating metal dopants, the toughness of the ceramic matrix can be enhanced without compromising its inherent hardness. In this study, TiB2 films with different nickel contents (0–32.22 at.%) were fabricated through radio frequency magnetron sputtering. The microstructure, chemical composition, phase structure, and mechanical properties were analyzed using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and nanoindentation tester. The pure TiB2 film exhibited (0001) and (0002) peaks; however, the addition of nickel resulted in broadening of the (0001) peak and disappearance of the (0002) peak, and no crystalline nickel or other nickel-containing phases could be identified. It was found that the incorporation of nickel refines the grain structure of titanium diboride, with nickel present in an amorphous form at the boundaries of titanium diboride, thereby forming a wrapped structure. The enrichment of nickel at the grain boundary becomes more pronounced as the nickel content is further increased, which hinders the growth of TiB2 grains, resulting in the thinning of columnar crystals and formation of nanocrystalline in the film, and the coating hardness remains above 20 GPa, when the nickel content is less than 10.83 at.%. With the increase in nickel content, titanium diboride exhibited a tendency to form an amorphous structure, while nickel became increasingly enriched at the boundaries, and the coating hardness and elastic modulus decreased. The wrapped microstructure could absorb the energy generated by compressive shear stress through plastic deformation, which should be beneficial to improve the toughness of the coatings. The addition of nickel enhanced the adhesion between the film and substrate while reducing the friction coefficient of the film. Specifically, when the nickel content reached 4.26 at.%, a notable enhancement in both nanohardness and toughness was observed for nanocomposite films. Full article
(This article belongs to the Special Issue Design and Applications of Heterogeneous Nanostructured Materials)
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13 pages, 3309 KiB  
Article
Improved Ferroelectric and Magnetic Properties of Bismuth Ferrite-Based Ceramics by Introduction of Non-Isovalent Ions and Grain Engineering
by Ting Wang, Huojuan Ye, Xiaoling Wang, Yuhan Cui, Haijuan Mei, Shenhua Song, Zhenting Zhao, Meng Wang, Pitcheri Rosaiah and Qing Ma
Nanomaterials 2025, 15(3), 215; https://doi.org/10.3390/nano15030215 - 29 Jan 2025
Cited by 1 | Viewed by 894
Abstract
Single-phase multiferroics exhibiting ferroelectricity and ferromagnetism are considered pivotal for advancing next-generation multistate memories, spintronic devices, sensors, and logic devices. In this study, the magnetic and electric characteristics of bismuth ferrite (BiFeO3) ceramics were enhanced through compositional design and grain engineering. [...] Read more.
Single-phase multiferroics exhibiting ferroelectricity and ferromagnetism are considered pivotal for advancing next-generation multistate memories, spintronic devices, sensors, and logic devices. In this study, the magnetic and electric characteristics of bismuth ferrite (BiFeO3) ceramics were enhanced through compositional design and grain engineering. BiFeO3 ceramic was co-substituted by neodymium (Nd) and niobium (Nb), two non-isovalent elements, via the spark plasma sintering process using phase-pure powder prepared via sol-gel as the precursor. The symmetry of the sintered Nd–Nb co-doped samples changed from R3c to Pnma, accompanied by a decrease in the loss tangent, grain size, and leakage current density. The reduction in the leakage current density of the co-doped samples was ~three orders of magnitude. Moreover, ferroelectric, dielectric, and magnetic properties were substantially improved. The remanent polarization and magnetization values of the optimized Nd–Nb co-doped BiFeO3 sample were 3.12 μC cm−2 and 0.15 emu g−1, respectively. The multiferroic properties were enhanced based on multiple factors such as structural distortion caused by co-doping, grain size reduction, suppression of defect charges via donor doping, space-modulated spin structure disruption, and an increase in magnetic ions. The synergistic approach of composition design and grain engineering sets a paradigm for the advancement of multiferroic materials. Full article
(This article belongs to the Special Issue Design and Applications of Heterogeneous Nanostructured Materials)
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12 pages, 6442 KiB  
Article
Interface Optimization and Thermal Conductivity of Cu/Diamond Composites by Spark Plasma Sintering Process
by Junfeng Zhao, Hao Su, Kai Li, Haijuan Mei, Junliang Zhang and Weiping Gong
Nanomaterials 2025, 15(1), 73; https://doi.org/10.3390/nano15010073 - 6 Jan 2025
Viewed by 963
Abstract
Cu/Diamond (Cu/Dia) composites are regarded as next-generation thermal dissipation materials and hold tremendous potential for use in future high-power electronic devices. The interface structure between the Cu matrix and the diamond has a significant impact on the thermophysical properties of the composite materials. [...] Read more.
Cu/Diamond (Cu/Dia) composites are regarded as next-generation thermal dissipation materials and hold tremendous potential for use in future high-power electronic devices. The interface structure between the Cu matrix and the diamond has a significant impact on the thermophysical properties of the composite materials. In this study, Cu/Dia composite materials were fabricated using the Spark Plasma Sintering (SPS) process. The results indicate that the agglomeration of diamond particles decreases with increasing particle size and that a uniform distribution is achieved at 200 μm. With an increase in the sintering temperature, the interface bonding is first optimized and then weakened, with the optimal sintering temperature being 900 °C. The addition of Cr to the Cu matrix leads to the formation of Cr7C3 after sintering, which enhances the relative density and bonding strength at the interface, transitioning it from a physical bond to a metallurgical bond. Optimizing the diamond particle size increased the thermal conductivity from 310 W/m K to 386 W/m K, while further optimizing the interface led to a significant increase to 516 W/m K, representing an overall improvement of approximately 66%. Full article
(This article belongs to the Special Issue Design and Applications of Heterogeneous Nanostructured Materials)
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13 pages, 3746 KiB  
Article
A Hierarchical Core-Shell Structure of NiO@Cu2O-CF for Effective Non-Enzymatic Electrochemical Glucose Detection
by Yueyun Huang, Jiahua You, Yingru Ding, Yun Xie, Ting Wang, Fanglong Zhu, Weiping Gong and Zhenting Zhao
Nanomaterials 2025, 15(1), 47; https://doi.org/10.3390/nano15010047 - 30 Dec 2024
Viewed by 775
Abstract
Non-enzymatic glucose detection is an effective strategy to control the blood glucose level of diabetic patients. A novel hierarchical core–shell structure of nickel hydroxide shell coated copper hydroxide core based on copper foam (Ni(OH)2@Cu(OH)2-CF) was fabricated and derived from [...] Read more.
Non-enzymatic glucose detection is an effective strategy to control the blood glucose level of diabetic patients. A novel hierarchical core–shell structure of nickel hydroxide shell coated copper hydroxide core based on copper foam (Ni(OH)2@Cu(OH)2-CF) was fabricated and derived from NiO@Cu2O-CF for glucose sensing. Cyclic voltammetry and amperometry experiments have demonstrated the efficient electrochemical catalysis of glucose under alkaline conditions. The measurement displays that the fabricated sensor exhibits a detection scale of 0.005–4.5 mM with a detection sensitivity of 4.67 µA/µM/cm2. It has remarkable response/recovery times in respect of 750 μM glucose (1.0 s/3.5 s). Moreover, the NiO@Cu2O-CF shows significant selectivity, reliable reproducibility and long-term stability for glucose determination, suggesting it is a suitable candidate for further applications. Full article
(This article belongs to the Special Issue Design and Applications of Heterogeneous Nanostructured Materials)
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11 pages, 10684 KiB  
Article
Effect of Bias Voltage on the Microstructure and Photoelectric Properties of W-Doped ZnO Films
by Haijuan Mei, Wanli Wang, Junfeng Zhao, Weilong Zhong, Muyi Qiu, Jiayang Xu, Kailin Gao, Ge Liu, Jianchu Liang and Weiping Gong
Nanomaterials 2024, 14(24), 2050; https://doi.org/10.3390/nano14242050 - 21 Dec 2024
Viewed by 761
Abstract
W-doped ZnO (WZO) films were deposited on glass substrates by using RF magnetron sputtering at different substrate bias voltages, and the relationships between microstructure and optical and electrical properties were investigated. The results revealed that the deposition rate of WZO films first decreased [...] Read more.
W-doped ZnO (WZO) films were deposited on glass substrates by using RF magnetron sputtering at different substrate bias voltages, and the relationships between microstructure and optical and electrical properties were investigated. The results revealed that the deposition rate of WZO films first decreased from 8.8 to 7.1 nm/min, and then increased to 11.5 nm/min with the increase in bias voltage. After applying a bias voltage to the substrate, the bombardment effect of sputtered ions was enhanced, and the films transformed from a smooth surface into a compact and rough surface. All the films exhibited a hexagonal wurtzite structure with a strong (002) preferred orientation and grew along the c-axis direction. When the bias voltage increased, both the residual stress and lattice parameter of the films gradually increased, and the maximum grain size of 43.4 nm was achieved at −100 V. When the bias voltage was below −300 V, all the films exhibited a high average transmittance of ~90% in the visible light region. As the bias voltage increased, the sheet resistance and resistivity of the films initially decreased and then gradually increased. The highest FOM of 5.8 × 10−4 Ω−1 was achieved at −100 V, possessing the best comprehensive photoelectric properties. Full article
(This article belongs to the Special Issue Design and Applications of Heterogeneous Nanostructured Materials)
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9 pages, 5136 KiB  
Article
Research on the Microstructure, Mechanical Properties and Strengthening Mechanism of Nanocrystalline Al-Mo Alloy Films
by Ying Wang, Huanqing Xu, Yulan Chen, Xiaoben Qi and Ning Zhong
Nanomaterials 2024, 14(24), 1990; https://doi.org/10.3390/nano14241990 - 12 Dec 2024
Viewed by 628
Abstract
In this work, the Al-Mo nanocrystalline alloy films with Mo contents ranging from 0–10.5 at.% were prepared via magnetron co-sputtering technology. The composition and microstructure of alloy thin films were studied using XRD, TEM, and EDS. The mechanical behaviors were tested through nanoindentation. [...] Read more.
In this work, the Al-Mo nanocrystalline alloy films with Mo contents ranging from 0–10.5 at.% were prepared via magnetron co-sputtering technology. The composition and microstructure of alloy thin films were studied using XRD, TEM, and EDS. The mechanical behaviors were tested through nanoindentation. The weights of each strengthening factor were calculated and the strengthening mechanism of alloy thin films was revealed. The results indicate that a portion of Mo atoms exist in the Al lattice, forming a solid solution of Mo in Al. The other part of Mo atoms tends to segregate at the grain boundaries, and this segregation becomes more pronounced with an increase in Mo content. There are no compounds or second phases present in any alloy films. As the Mo element content increases, the grain size of the alloy films gradually decreases. The hardness of pure aluminum film is 2.2 GPa. The hardness increases with an increase in Mo content. When the Mo content is 10.5 at.%, The hardness of the film increases to a maximum value of 4.9 GPa. The fine grain (∆Hgb), solid solution (∆Hss), and nanocrystalline solute pinning (∆Hnc,ss) are the three main reasons for the increase in the hardness of alloy thin films. The contribution of ∆Hgb is the largest, accounting for over 60% of the total, while the contribution of ∆Hss accounts for about 30%, ranking second. The rest of the increase is due to ∆Hnc,ss. Full article
(This article belongs to the Special Issue Design and Applications of Heterogeneous Nanostructured Materials)
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13 pages, 4502 KiB  
Article
Application of Polyvinyl Alcohol–Ethylene Glycol Hydrogel Technology for Removing Animal Glue in Book Restoration Based on Fluorescent Labeling Evaluation
by Jia Wang, Yuting Xu, Canxin Tian, Yunjiang Yu and Changwei Zou
Nanomaterials 2024, 14(23), 1878; https://doi.org/10.3390/nano14231878 - 22 Nov 2024
Viewed by 876
Abstract
This study developed a novel material based on polyvinyl alcohol–ethylene glycol (PVA-EG) hydrogel and systematically evaluated its potential application in the removal of animal glue from book surfaces. The microstructure, surface properties, and mechanical characteristics of the PVA-EG hydrogel were analyzed using X-ray [...] Read more.
This study developed a novel material based on polyvinyl alcohol–ethylene glycol (PVA-EG) hydrogel and systematically evaluated its potential application in the removal of animal glue from book surfaces. The microstructure, surface properties, and mechanical characteristics of the PVA-EG hydrogel were analyzed using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), contact angle measurements, a universal testing machine, and a dynamic mechanical analysis (DMA). The introduction of ethylene glycol (EG) could weaken hydrogen bonding interactions between PVA chains to enhance the molecular chain flexibility of the hydrogel. Notably, the 10% PVA-EG hydrogel shows better crystallinity, higher hydrophilicity, and optimal balance between mechanical strength and flexibility compared to pure PVA, which is conducive to improving the efficiency of the removal of animal glue. Additionally, the effectiveness of the process of removing animal glue was verified by real-time monitoring using europium nitrate at a concentration of 0.4% (w/v) as a fluorescent marker. Such hydrogels with high mechanical properties, strong surface hydrophilicity, good removal efficiency, and gentle treatment characteristics have potential applications in the restoration of cultural heritage. Full article
(This article belongs to the Special Issue Design and Applications of Heterogeneous Nanostructured Materials)
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13 pages, 3286 KiB  
Article
Improving the NO2 Gas Sensing Performances at Room Temperature Based on TiO2 NTs/rGO Heterojunction Nanocomposites
by Yan Ling, Yunjiang Yu, Canxin Tian and Changwei Zou
Nanomaterials 2024, 14(22), 1844; https://doi.org/10.3390/nano14221844 - 18 Nov 2024
Cited by 2 | Viewed by 999
Abstract
The development of energy-efficient, sensitive, and reliable gas sensors for monitoring NO2 concentrations has garnered considerable attention in recent years. In this manuscript, TiO2 nanotube arrays/reduced graphene oxide nanocomposites with varying rGO contents (TiO2 NTs/rGO) were synthesized via a two-step [...] Read more.
The development of energy-efficient, sensitive, and reliable gas sensors for monitoring NO2 concentrations has garnered considerable attention in recent years. In this manuscript, TiO2 nanotube arrays/reduced graphene oxide nanocomposites with varying rGO contents (TiO2 NTs/rGO) were synthesized via a two-step method for room temperature NO2 gas detection. From SEM and TEM images, it is evident that the rGO sheets not only partially surround the TiO2 nanotubes but also establish interconnection bridges between adjacent nanotubes, which is anticipated to enhance electron–hole separation by facilitating electron transfer. The optimized TiO2 NTs/rGO sensor demonstrated a sensitive response of 19.1 to 1 ppm of NO2, a 5.26-fold improvement over the undoped TiO2 sensor. Additionally, rGO doping significantly enhanced the sensor’s response/recovery times, reducing them from 24 s/42 s to 18 s/33 s with just 1 wt.% rGO. These enhancements are attributed to the increased specific surface area, higher concentration of chemisorbed oxygen species, and the formation of p-n heterojunctions between TiO2 and rGO within the nanocomposites. This study provides valuable insights for the development of TiO2/graphene-based gas sensors for detecting oxidizing gases at room temperature. Full article
(This article belongs to the Special Issue Design and Applications of Heterogeneous Nanostructured Materials)
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20 pages, 7608 KiB  
Article
Anti-Sintering Behavior of GYYSZ, Thermophysical Properties, and Thermal Shock Behavior of Thermal Barrier Coating with YSZ/Composite/GYYSZ System by Atmospheric Plasma Spraying
by Chunxia Jiang, Rongbin Li, Feng He, Zhijun Cheng, Wenge Li and Yuantao Zhao
Nanomaterials 2024, 14(22), 1787; https://doi.org/10.3390/nano14221787 - 7 Nov 2024
Cited by 2 | Viewed by 1218
Abstract
In this study, Gd2O3 and Yb2O3 co-doped YSZ (GYYSZ) ceramic coatings were prepared via atmospheric plasma spraying (APS). The GYYSZ ceramic coatings were subjected to heat treatment at different temperatures for 5 h to analyze their high-temperature [...] Read more.
In this study, Gd2O3 and Yb2O3 co-doped YSZ (GYYSZ) ceramic coatings were prepared via atmospheric plasma spraying (APS). The GYYSZ ceramic coatings were subjected to heat treatment at different temperatures for 5 h to analyze their high-temperature phase stability and sintering resistance. The thermophysical properties of GYYSZ, YSZ, and composite coatings were compared. Three types of thermal barrier coatings (TBCs) were designed: GYYSZ (TBC-1), YSZ/GYYSZ (TBC-2), and YSZ/Composite/GYYSZ (TBC-3). The failure mechanisms of these three TBCs were investigated. The results indicate that both the powder and the sprayed GYYSZ primarily maintain a homogeneous cubic phase c-ZrO2, remaining stable at 1500 °C after annealing. The sintering and densification of the coatings are influenced by the annealing temperature; higher temperatures lead to faster sintering rates. At 1500 °C, the grain size and porosity of GYYSZ are 4.66 μm and 9.9%, respectively. At 1000 °C, the thermal conductivity of GYYSZ is 1.35 W·m−1 K−1, which is 44% lower than that of YSZ. The thermal conductivity of the composite material remains between 1.79 W·m−1 K−1 and 1.99 W·m−1 K−1 from room temperature to 1000 °C, positioned between GYYSZ and YSZ. In the TBC thermal shock water quenching experiment, TBC-3 demonstrated an exceptionally long thermal shock lifetime of 246.3 cycles, which is 5.8 times that of TBC-1 and 1.8 times that of TBC-2. The gradient coating structure effectively reduces the thermal mismatch stress between layers, while the dense surface microcracks provide a certain toughening effect. Failure analysis of the TBC reveals that TBC-3 exhibits a mixed failure mode characterized by both spallation and localized peeling. The ultimate failure was attributed to the propagation of transverse cracks during the final stage of water quenching, which led to the eventual spallation of the ceramic blocks. Full article
(This article belongs to the Special Issue Design and Applications of Heterogeneous Nanostructured Materials)
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