Advances in Metal Matrix Composite Coatings and Layers: Microstructure, Physicochemical and Mechanical Properties

A special issue of Coatings (ISSN 2079-6412). This special issue belongs to the section "Surface Characterization, Deposition and Modification".

Deadline for manuscript submissions: 15 June 2024 | Viewed by 14237

Special Issue Editors


E-Mail Website
Guest Editor
Faculty of Mechanical Engineering, Poznan University of Technology, Poznan, Poland
Interests: metal matrix composite coatings; carbides; microstructure; laser processing; laser cladding; wear resistance; hard materials
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
Faculty of Materials Engineering and Technical Physics, Poznan University of Technology, Poznan, Poland
Interests: laser remelting; laser alloying; properties and application of carbide and boride layers; microstructure; microhardness; anti-wear layers; wear resistance; surface roughness
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Metal matrix composite coatings (MMC coatings) and composite layers are unique compared to conventional coatings that do not retain a composite character. Both the type of matrix and type of reinforcing phase, as well as the production method, have an influence on the final properties of coatings and their application in the industry. High hardness and heat resistance of reinforcing phase (such as carbides or borides) contribute to increasing the performance parameters. This kind of coatings may be obtained using high-energy methods such as laser cladding, laser alloying or laser metal deposition, as well as using other surfacing methods or sintering. During all these processes, interesting physicochemical phenomena can be observed. The mechanical and microstructural properties obtained via these innovative processes are very important and affect the application of these coatings in the industry.

We invite researchers to contribute to this Special Issue on “Advances in Metal Matrix Composite Coatings and Layers: Microstructure, Physicochemical and Mechanical Properties”, which is intended to serve as a unique multidisciplinary forum focused on the production, properties, as well as applications of composite coatings and layers containing reinforcing hard phases with particular emphasis on corrosion and wear resistance. In particular, the topic of interest includes but is not limited to:

  • Modern production methods of composite coatings;
  • Laser processing of coatings;
  • Microstructural analysis of modern composite coatings;
  • Laser cladding and laser metal deposition;
  • Laser alloying;
  • High energy method in coatings production (plasma, HVOF, etc.);
  • Diffusion surface layers of a composite nature;
  • Scanning electron microscopy in coating testing;
  • Additive manufacturing;
  • Carbides and borides in coatings;
  • Corrosion resistance of coatings;
  • Wear resistance of coatings;
  • Phase and chemical composition analysis of coatings;
  • Microhardness and nanoindentation analysis.

Dr. Dariusz Bartkowski
Dr. Aneta Bartkowska
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. Coatings is an international peer-reviewed open access monthly 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 2600 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.

Published Papers (12 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

15 pages, 13318 KiB  
Article
Fabrication of Nanostructures Consisting of Composite Nanoparticles by Open-Air PLD
by Anna Og Dikovska, Daniela Karashanova, Genoveva Atanasova, Georgi Avdeev, Petar Atanasov and Nikolay N. Nedyalkov
Coatings 2024, 14(5), 527; https://doi.org/10.3390/coatings14050527 - 24 Apr 2024
Viewed by 436
Abstract
We present a two-step physical method for the fabrication of composite nanoparticle-based nanostructures. The proposed method is based on the pulsed laser deposition (PLD) technique performed sequentially in vacuum and in air. As a first step, thin-alloyed films of iron with noble metal [...] Read more.
We present a two-step physical method for the fabrication of composite nanoparticle-based nanostructures. The proposed method is based on the pulsed laser deposition (PLD) technique performed sequentially in vacuum and in air. As a first step, thin-alloyed films of iron with noble metal were deposited by PLD in vacuum. The films were prepared by ablation of a mosaic target formed by equal iron and gold sectors. As a second step, the as-prepared alloyed films were ablated in air at atmospheric pressure as the laser beam scanned their surface. Two sets of experiments were performed in the second step, namely, by applying nanosecond (ns) and picosecond (ps) laser pulses for ablation. The structure, microstructure, morphology, and optical properties of the samples obtained were studied with respect to the laser ablation regime applied. The implementation of the ablation process in open air resulted in the formation of nanoparticle and/or nanoparticle aggregates in the plasma plume regardless of the ablation regime applied. These nanoparticles and/or nanoaggregates deposited on the substrate formed a complex porous structure. It was found that ablating FeAu films in air by ns pulses resulted in the fabrication of alloyed nanoparticles, while ablation by ps laser pulses results in separation of the metals in the alloy and further oxidation of Fe. In the latter case, the as-deposited structures also contain core–shell type nanoparticles, with the shell consisting of Fe-oxide phase. The obtained structures, regardless of the ablation regime applied, demonstrate a red-shifted plasmon resonance with respect to the plasmon resonance of pure Au nanoparticles. Full article
Show Figures

Figure 1

12 pages, 2769 KiB  
Article
A Visualization Experiment on Icing Characteristics of a Saline Water Droplet on the Surface of an Aluminum Plate
by Yingwei Zhang, Xinpeng Zhou, Weihan Shi, Jiarui Chi, Yan Li and Wenfeng Guo
Coatings 2024, 14(2), 155; https://doi.org/10.3390/coatings14020155 - 23 Jan 2024
Viewed by 663
Abstract
When the offshore device, such as an offshore wind turbine, works in winter, ice accretion often occurs on the blade surface, which affects the working performance. To explore the icing characteristics on a microscale, the freezing characteristics of a water droplet with salinity [...] Read more.
When the offshore device, such as an offshore wind turbine, works in winter, ice accretion often occurs on the blade surface, which affects the working performance. To explore the icing characteristics on a microscale, the freezing characteristics of a water droplet with salinity were tested in the present study. A self-developed icing device was used to record the icing process of a water droplet, and a water droplet with a volume of 5 μL was tested under different salinities and temperatures. The effects of salinity and temperature on the profile of the iced water droplet, such as the height and contact diameter, were analyzed. As the temperature was constant, along with the increase in salinity, the height of the iced water droplet first increased and then decreased, and the contact diameter decreased. The maximum height of the iced water droplet was 1.21 mm, and the minimum contact diameter was 3.67 mm. With the increase in salinity, the icing time of the water droplet increased, yet a minor effect occurred under low temperatures such as −18 °C. Based on the experimental results, the profile of the iced water droplet was fitted using the polynomial method, with a coefficient of determination (R2) higher than 0.99. Then the mathematical model of the volume of the iced water droplet was established. The volume of the iced water droplet decreased along with temperature and increased along with salinity. The largest volume was 4.1 mm3. The research findings provide a foundation for exploring the offshore device icing characteristics in depth. Full article
Show Figures

Figure 1

13 pages, 3189 KiB  
Article
Exploring the Influence of the Deposition Parameters on the Properties of NiTi Shape Memory Alloy Films with High Nickel Content
by André V. Fontes, Patrícia Freitas Rodrigues, Daniela Santo and Ana Sofia Ramos
Coatings 2024, 14(1), 138; https://doi.org/10.3390/coatings14010138 - 20 Jan 2024
Viewed by 766
Abstract
NiTi shape memory alloy films were prepared by magnetron sputtering using a compound NiTi target and varying deposition parameters, such as power density, pressure, and deposition time. To promote crystallization, the films were heat treated at a temperature of 400 °C for 1 [...] Read more.
NiTi shape memory alloy films were prepared by magnetron sputtering using a compound NiTi target and varying deposition parameters, such as power density, pressure, and deposition time. To promote crystallization, the films were heat treated at a temperature of 400 °C for 1 h. For the characterization, scanning electron microscopy, energy dispersive X-ray spectroscopy, atomic force microscopy, synchrotron X-ray diffraction, and nanoindentation techniques were used on both as-deposited and heat-treated films. Apart from the morphology and hardness of the as-deposited films that depend on the deposition pressure, the power applied to the target and the deposition pressure did not seem to significantly influence the characteristics of the NiTi films studied. After heat treatment, austenitic (B2) crystalline superelastic films with exceptionally high nickel content (~60 at.%) and vein-line cross-section morphology were produced. The crystallization of the films resulted in an increase in hardness, Young’s modulus, and elastic recovery. Full article
Show Figures

Figure 1

15 pages, 12854 KiB  
Article
Spray Parameters and Coating Microstructure Relationship in Suspension Plasma Spray TiO2 Coatings
by Garima Mittal, Nigar Gul Malik, Arunima Bhuvanendran Nair Jayakumari, David Martelo, Namrata Kale and Shiladitya Paul
Coatings 2023, 13(12), 1984; https://doi.org/10.3390/coatings13121984 - 22 Nov 2023
Viewed by 814
Abstract
In recent years, there has been growing interest in thermal spray techniques using suspension or solution-based coatings. These techniques offer precise control over particle size and microstructure, improving feedstock flowability and allowing for high-quality coating customization. Spray parameters, such as stand-off distance (SOD) [...] Read more.
In recent years, there has been growing interest in thermal spray techniques using suspension or solution-based coatings. These techniques offer precise control over particle size and microstructure, improving feedstock flowability and allowing for high-quality coating customization. Spray parameters, such as stand-off distance (SOD) and feedstock flow rate, can alter the performance and characteristics of these coatings. Geothermal power plant heat exchangers often face issues like corrosion, scaling, and fouling. The literature suggests that these issues could be mitigated, at least in part, by the use of spray coatings. In this study, TiO2 coatings were applied on a carbon steel substrate using suspension plasma spray (SPS) to enhance the performance of geothermal heat exchanger materials. The impact of SOD (50, 75, and 100 mm) and feedstock flow rate (10, 20, and 30 mL/min) on these coatings was examined through various techniques, including scanning electron microscope (SEM), profilometry, X-ray diffraction (XRD), and adhesion testing. The results demonstrated that coatings deposited using a 10 mL/min feedstock flow rate were well adhered to the substrate due to the efficient melting of the coating material, but as the SOD and feedstock flow rate increased due to poor thermal and kinetic energy exchange between the torch and feedstock particles, adhesion between the coating and substrate decreased. Full article
Show Figures

Figure 1

15 pages, 11904 KiB  
Article
The Roughness Effect on the Preparation of Durable Superhydrophobic Silver-Coated Copper Foam for Efficient Oil/Water Separation
by Aikaterini Baxevani, Fani Stergioudi and Stefanos Skolianos
Coatings 2023, 13(11), 1851; https://doi.org/10.3390/coatings13111851 - 27 Oct 2023
Cited by 2 | Viewed by 938
Abstract
In recent decades, there has been a significant interest in superhydrophobic coatings owing to their exceptional properties. In this research work, a superhydrophobic coating was developed on copper foams with a different roughness via immersion in AgNO3 and stearic acid solutions. The [...] Read more.
In recent decades, there has been a significant interest in superhydrophobic coatings owing to their exceptional properties. In this research work, a superhydrophobic coating was developed on copper foams with a different roughness via immersion in AgNO3 and stearic acid solutions. The resulting foams exhibited water contact angles of 180°. Notably, surface roughness of the substrate influenced the development of silver dendrites and stearic acid morphologies, leading to different structures on rough and smooth copper foams. Separation efficiency was maintained above 94% for various pollutants, suggesting good stability and durability, irrespective of the substrate’s roughness. Conversely, absorption capacity was influenced by surface roughness of the substrate, with smooth copper foams demonstrating higher absorption values, primarily due to its uniform porosity and microstructure, which allowed for efficient retention of pollutants. Both copper foams exhibited excellent thermal and chemical stability and maintained their hydrophobic properties even after a 40 h exposure to harsh conditions. Mechanical durability of modified copper foams was tested by dragging and in ultrasounds, exhibiting promising results. The samples with the smooth substrate demonstrated improved coating stability. Full article
Show Figures

Figure 1

20 pages, 19407 KiB  
Article
Fe/TaC Coatings Produced on 145Cr6 Steel by Laser Alloying—Manufacturing Parameters and Material Characterization
by Dariusz Bartkowski and Aneta Bartkowska
Coatings 2023, 13(8), 1432; https://doi.org/10.3390/coatings13081432 - 15 Aug 2023
Viewed by 985
Abstract
This paper focuses on Fe/TaC composite coatings produced on 145Cr6 steel by laser alloying a TaC precoat in paste form. Fe/TaC coatings were produced in two consecutive steps. The first stage was the application of a precoat in paste form made from tantalum [...] Read more.
This paper focuses on Fe/TaC composite coatings produced on 145Cr6 steel by laser alloying a TaC precoat in paste form. Fe/TaC coatings were produced in two consecutive steps. The first stage was the application of a precoat in paste form made from tantalum carbide and water glass on a steel substrate. Three TaC precoat thicknesses were produced: 30 µm, 60 µm and 90 µm. In the second step, the TaC precoat was remelted on a steel substrate using a 3 kW rated diode laser beam. A constant laser beam scanning speed of 3 m/min and three laser beam powers were used: 500 W, 800 W and 1100 W. In the study, microstructure, microhardness, chemical and phase composition and wear resistance were tested. The aim of the research was to check the possibility of producing composite coatings in which the reinforcing phase will be TaC, and the role of the matrix will be played by the material from the substrate. It was found that it is possible to produce the continuous composite coatings by remelting the TaC precoat with steel substrate. As microhardness increased, so did wear resistance. The coating microhardness obtained ranged from about 750 to 850 HV0.05 depending on the parameters used. Full article
Show Figures

Figure 1

14 pages, 4647 KiB  
Article
Anisotropy of the Tribological Performance of Periodically Oxidated Laser-Induced Periodic Surface Structures
by Pavels Onufrijevs, Liga Grase, Juozas Padgurskas, Mindaugas Rukanskis, Ramona Durena, Dieter Willer, Mairis Iesalnieks, Janis Lungevics, Jevgenijs Kaupuzs, Raimundas Rukuiža, Rita Kriūkienė, Yuliya Hanesch and Magdalena Speicher
Coatings 2023, 13(7), 1199; https://doi.org/10.3390/coatings13071199 - 04 Jul 2023
Viewed by 1014
Abstract
Laser-induced periodic surface structures (LIPSS) enable advanced surface functionalization with broad applications in various fields such as micro- and nanoelectronics, medicine, microbiology, tribology, anti-icing systems, and more. This study demonstrates the possibility of achieving anisotropy in the tribological behavior of C45-grade steel structured [...] Read more.
Laser-induced periodic surface structures (LIPSS) enable advanced surface functionalization with broad applications in various fields such as micro- and nanoelectronics, medicine, microbiology, tribology, anti-icing systems, and more. This study demonstrates the possibility of achieving anisotropy in the tribological behavior of C45-grade steel structured by nanosecond laser radiation using the LIPSS method. The lateral surface of the steel roller was irradiated with a pulsed Nd:YAG laser at an optimum intensity I = 870 MW/cm2 for the formation of LIPSS. Two sets of samples were formed with LIPSS that were perpendicular and parallel to the roller’s rotational motion direction. The Raman intensity maps revealed that the LIPSS structure consisted of periodically arranged oxides at the top of hills. At the same time, the valleys of the LIPSS structures were almost not oxidized. These results correlated well with scanning electron microscopy energy dispersive X-ray spectroscopy mapping and atomic force microscopy measurements. A comparison of Raman and X-ray photoelectron spectroscopy spectra revealed that both the magnetite phase and traces of the hematite phase were present on the surface of the samples. Tribological tests were performed in two cycles with periodic changes in the normal clamping force and sliding speed. It was found that the LIPSS structures which were formed perpendicularly to the sliding direction on the roller had a significantly greater impact on the friction processes. Structures oriented perpendicular to the direction of motion had a positive influence on reducing the energy consumption of a friction process as well as increasing the wear resistance compared to LIPSS formed parallel to the direction of motion or ones having a non-texturized surface. Laser texturing to produce LIPSS perpendicular to the direction of motion could be recommended for friction pairs operating under low-load conditions. Full article
Show Figures

Graphical abstract

23 pages, 8003 KiB  
Article
Microstructure Refinement of EB-PVD Gadolinium Zirconate Thermal Barrier Coatings to Improve Their CMAS Resistance
by Christoph Mikulla, Lars Steinberg, Philipp Niemeyer, Uwe Schulz and Ravisankar Naraparaju
Coatings 2023, 13(5), 905; https://doi.org/10.3390/coatings13050905 - 11 May 2023
Cited by 1 | Viewed by 1756
Abstract
Rare-earth zirconates are proven to be very effective in restricting the CMAS attack against thermal barrier coatings (TBCs) by forming quick crystalline reaction products that seal the porosity against infiltration. The microstructural effects on the efficacy of Electron Beam-Physical Vapor Deposition gadolinium zirconate [...] Read more.
Rare-earth zirconates are proven to be very effective in restricting the CMAS attack against thermal barrier coatings (TBCs) by forming quick crystalline reaction products that seal the porosity against infiltration. The microstructural effects on the efficacy of Electron Beam-Physical Vapor Deposition gadolinium zirconate (EB-PVD GZO) against CMAS attack are explored in this study. Four distinct GZO microstructures were manufactured and the response of two selected GZO variants to different CMAS and volcanic ash melts was studied for annealing times between 10 min and 50 h at 1250 °C. A significant variation in the microstructural characteristics was achieved by altering substrate temperature and rotation speed. A refined microstructure with smaller intercolumnar gaps and long feather arms lowered the CMAS infiltration by 56%–72%. Garnet phase, which formed as a continuous layer on top of apatite and fluorite, is identified as a beneficial reaction product that improves the CMAS resistance. Full article
Show Figures

Figure 1

12 pages, 3027 KiB  
Article
Enhancing Photovoltaic Performance and Stability of Perovskite Solar Cells through Single-Source Evaporation and CsPbBr3 Quantum Dots Incorporation
by Yuanzhe Kou, Jianxiao Bian, Xiaonan Pan and Jinchang Guo
Coatings 2023, 13(5), 863; https://doi.org/10.3390/coatings13050863 - 01 May 2023
Cited by 1 | Viewed by 2091
Abstract
This study investigates the potential of inorganic perovskite CsPbBr3 as a photovoltaic material, highlighting its superior stability compared to that of organic–inorganic hybrid perovskite materials. Conventional methods for preparing CsPbBr3 perovskite films, such as the two-step method and the dual-source thermal [...] Read more.
This study investigates the potential of inorganic perovskite CsPbBr3 as a photovoltaic material, highlighting its superior stability compared to that of organic–inorganic hybrid perovskite materials. Conventional methods for preparing CsPbBr3 perovskite films, such as the two-step method and the dual-source thermal evaporation method, face challenges in obtaining high-purity films due to the decomposition of precursor films and the formation of multiple heterogeneous phases. To address this issue, we synthesized CsPbBr3 powder material using thermal evaporation deposition, which effectively suppressed decomposition and the formation of heterogeneous phases. Consequently, we achieved uniform and dense CsPbBr3 perovskite films. By incorporating energy-band engineering modification with CsPbBr3 quantum dots (QDs), the all-inorganic perovskite solar cells (PSCs) attained a power conversion efficiency (PCE) of 7.01% under standard solar illumination conditions. The device PCE remained at 93% of its initial efficiency under 30% relative humidity conditions for over 100 days, showcasing its durability. The developed method produced an average grain size of 800 nm, resulting in a smooth and uniform film surface, thereby demonstrating the method’s high repeatability. Additionally, the optimized PSCs exhibited a high open-circuit voltage (VOC) with the champion device reaching a VOC of 1.38 V and a PCE of 7.01%. This research presents a robust, efficient, and cost-effective approach for fabricating high-quality all-inorganic PSCs. Full article
Show Figures

Figure 1

16 pages, 6489 KiB  
Article
Investigating the Effects of Geometrical Parameters of Re-Entrant Cells of Aluminum 7075-T651 Auxetic Structures on Fatigue Life
by Amir Ghiasvand, Alireza Fayazi Khanigi, John William Grimaldo Guerrero, Hamed Aghajani Derazkola, Jacek Tomków, Anna Janeczek and Adrian Wolski
Coatings 2023, 13(2), 405; https://doi.org/10.3390/coatings13020405 - 10 Feb 2023
Cited by 2 | Viewed by 1593
Abstract
In this study, the effects of two geometrical parameters of the re-entrant auxetic cells, namely, internal cell angle (θ) and H/L ratio in which H is the cell height, and L is the cell length, have been studied on the variations [...] Read more.
In this study, the effects of two geometrical parameters of the re-entrant auxetic cells, namely, internal cell angle (θ) and H/L ratio in which H is the cell height, and L is the cell length, have been studied on the variations of Poisson’s ratio and fatigue life of Aluminum 7075-T6 auxetic structures. Five different values of both the H/L ratio and angle θ were selected. Numerical simulations and fatigue life predictions have been conducted through the use of ABAQUS (version 2022) and MSC Fatigue (version 11.0) software. Results revealed that increases in both the H/L ratio and angle θ improved the average value of Poisson’s ratio. Increasing the H/L ratio from 1 to 1.4 and θ from 50° to 70° increased the values of Poisson’s ratio, respectively, 7.7% and 80%. In all angles, increasing the H/L values decreased the fatigue life of the structures significantly. Furthermore, in all H/L values, an increment in θ caused a reduction in fatigue life. The effects of H/L and θ parameters on fatigue life were dominant in the low cycle fatigue regime. Results also showed that the H/L ratio parameter had greater influence as compared to the θ angle, and the structures with higher auxeticity experienced higher fatigue resistance. It was found that the auxetic property of the structure has a direct relationship with the fatigue resistance of the structure. In all samples, structures with greater auxetic property had higher fatigue resistance. Full article
Show Figures

Figure 1

17 pages, 6271 KiB  
Article
Automatic Recognition of Microstructures of Air-Plasma-Sprayed Thermal Barrier Coatings Using a Deep Convolutional Neural Network
by Xiao Shan, Tianmeng Huang, Lirong Luo, Jie Lu, Huangyue Cai, Junwei Zhao, Gang Sheng and Xiaofeng Zhao
Coatings 2023, 13(1), 29; https://doi.org/10.3390/coatings13010029 - 23 Dec 2022
Cited by 2 | Viewed by 1385
Abstract
Either to obtain desirable microstructures by adjusting processing parameters or to predict the properties of a thermal barrier coating (TBC) according to its microstructure, fast and reliable quantitation of the microstructure is imperative. In this research, a machine-learning-based approach—a deep convolution neural network [...] Read more.
Either to obtain desirable microstructures by adjusting processing parameters or to predict the properties of a thermal barrier coating (TBC) according to its microstructure, fast and reliable quantitation of the microstructure is imperative. In this research, a machine-learning-based approach—a deep convolution neural network (DCNN)—was established to accurately quantify the microstructure of air-plasma-sprayed (APS) TBCs based on 2D images. Four scanning electron microscopy (SEM) images (view field: 150 μm × 150 μm, image size: 3072 pixel × 3072 pixel) were taken and labeled to train the DCNN. After training, the DCNN could recognize correctly 98.5% of the pixels in the SEM images of typical APS TBCs. This study demonstrated that a small dataset of SEM images could be enough to train a DCNN, making it a powerful and feasible method for quantitively characterizing the microstructure osf APS TBCs. Full article
Show Figures

Figure 1

10 pages, 4155 KiB  
Article
Effect of Al2O3 Content on High-Temperature Oxidation Resistance of Ti3SiC2/Al2O3
by Yuhang Du, Qinggang Li, Sique Chen, Deli Ma, Baocai Pan, Zhenyu Zhang and Jinkai Li
Coatings 2022, 12(11), 1641; https://doi.org/10.3390/coatings12111641 - 29 Oct 2022
Viewed by 1184
Abstract
Considering the lack of an effective anti-oxidation protective layer for the oxidation process of Ti3SiC2, an in situ synthesis of Ti3SiC2 and Al2O3 was designed. Thermally stable Al2O3 was used [...] Read more.
Considering the lack of an effective anti-oxidation protective layer for the oxidation process of Ti3SiC2, an in situ synthesis of Ti3SiC2 and Al2O3 was designed. Thermally stable Al2O3 was used to improve the high-temperature oxidation resistance of Ti3SiC2. Samples without TiC were selected for the oxidation test, and the oxidation morphology and weight gain curves of the oxidized surface in air at 1400 °C are reported. The change in the oxidation behavior occurred 4 h after oxidation. The addition of Al2O3 changed the composition of the oxide layer and compensated for the lack of a dense protective layer during Ti3SiC2 oxidation. Moreover, after 4 h of oxidation, the newly generated Al2TiO5 and the composite layer formed by diffusion were the main reasons for the large difference in the final weight gain between the two sets of samples. Full article
Show Figures

Figure 1

Planned Papers

The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.

Title: Influence of the Stellite-6/(WC+TiC) pre-coat and diode laser beam parameters on changes in properties and microstructure in the surface layer of S355 steel after laser alloying
Authors: Bartkowski D., Bartkowska A., Przestacki D., Olszewska J
Affiliation: Faculty of Mechanical Engineering, Institute of Materials Technology, Poznan University of Technology, ul. Piotrowo 3, 61-138 Poznan, Poland
Abstract: The paper presents the study results of Stellite-6/(WC+TiC) coatings produced by laser alloying with different content of reinforcing phases (40%wt and 60%wt content of mixture WC+TiC). Coatings were produced on S355 steel using different laser beam power 600 W, 900 W and 1200 W. Obtained coatings were subjected to microhardness measurement, wear resistance tests, roughness profile before and after wear tests, chemical composition analysis and microstructure observation using light microscopy and scanning electron microscopy. It was found that for both types of coatings the higher microhardness and wear resistance in comparison to the substrate material were obtained. Rate of solidification had influence on obtained results of study.

Back to TopTop