Advances of Ceramic and Alloy Coatings

A special issue of Coatings (ISSN 2079-6412). This special issue belongs to the section "Corrosion, Wear and Erosion".

Deadline for manuscript submissions: closed (31 December 2023) | Viewed by 26057

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Special Issue Editors

School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China
Interests: high-entropy alloy; corrosion of alloy; coatings; electron microscopy
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Guest Editor
School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China
Interests: thermodynamic assessment; alloy design; phase equilibria

E-Mail Website
Guest Editor
School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China
Interests: thermodynamic assessment; alloy design; hot dip galvanizing; heat trement; surface modification; phase equilibria; high-entropy alloy

Special Issue Information

 

Dear Colleagues,

With the development of modern technology, advanced ceramics and alloy coatings have gradually become an important part of new materials and become important materials in the development of many high-tech fields. It has received great attention from various industrially developed countries. Advanced ceramics and alloys, which have a specific fine structure and a series of excellent properties (e.g., high strength, high hardness, wear resistance, corrosion resistance, high-temperature resistance, etc.), are widely used in various fields, such as national defense, chemical industry, metallurgy, electronics, machinery, aviation, aerospace, biomedicine and so on.

Thus, by including all types of substrates and coating technologies, this Special Issue aims to provide better assessments of the potential applications of different cermics and alloy coating technologies on different substrates.

Dr. Yi Yang
Dr. Xinming Wang
Prof. Dr. Fucheng Yin
Guest Editors

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Keywords

  • high-entroy alloy
  • coatings
  • corrosion
  • alloy design
  • ceramic

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Related Special Issue

Published Papers (13 papers)

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Research

15 pages, 5370 KiB  
Article
Microstructure and High-Temperature Properties of Cr3C2-25NiCr Nanoceramic Coatings Prepared by HVAF
by Zhiqiang Zhou, Dajun Duan, Shulan Li, Deen Sun, Jiahui Yong, Yongbing Jiang, Wu He and Jian Xu
Coatings 2023, 13(10), 1741; https://doi.org/10.3390/coatings13101741 - 7 Oct 2023
Cited by 1 | Viewed by 1402
Abstract
The study examines the microstructure and high-temperature properties of Cr3C2-25NiCr nanoceramic coatings on 316H high-temperature-resistant stainless steel that were prepared by high-velocity air–fuel spraying (HVAF) technology. The micromorphology, phase composition, fracture toughness, high-temperature hardness, high-temperature friction, and wear properties [...] Read more.
The study examines the microstructure and high-temperature properties of Cr3C2-25NiCr nanoceramic coatings on 316H high-temperature-resistant stainless steel that were prepared by high-velocity air–fuel spraying (HVAF) technology. The micromorphology, phase composition, fracture toughness, high-temperature hardness, high-temperature friction, and wear properties of the coating were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD), high-temperature Vickers hardness tester, high-temperature friction and wear tester, and surface profiler. The results show that the Cr3C2-25NiCr coating prepared by HVAF presents a typical thermal spraying coating structure, with a dense structure and a porosity of only 0.34%. The coating consists of a Cr3C2 hard phase, a NiCr bonding phase, and a small amount of Cr7C3 phase; The average microhardness of the coating at room temperature is 998.8 HV0.3, which is about five times higher than that of 316H substrate. The Weibull distribution of the coating is unimodal, showing stable mechanical properties. The average microhardness values of the coating at 450 °C, 550 °C, 650 °C, and 750 °C are 840 HV0.3, 811 HV0.3, 729 HV0.3, and 696 HV0.3 respectively. The average friction coefficient of the Cr3C2-25NiCr coating initially decreases and then increases with temperature. During high-temperature friction and wear, a dark gray oxide film forms on the coating surface. The formation speed of the oxide film accelerates with increasing temperature, shortening the running-in period of the coating. The oxide film acts as a lubricant, reducing the friction coefficient of the coating. The Cr3C2-25NiCr coating exhibits exceptional high-temperature friction and wear resistance, primarily through oxidative wear. The Cr3C2-25NiCr coating exhibits outstanding high-temperature friction and wear resistance, with oxidative wear being the primary wear mechanism at elevated temperatures. Full article
(This article belongs to the Special Issue Advances of Ceramic and Alloy Coatings)
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17 pages, 13591 KiB  
Article
The Effect of Pulling Speed on the Structure and Properties of DZ22B Superalloy Blades
by Bing Hu, Wei Xie, Wenhui Zhong, Dan Zhang, Xinming Wang, Jingxian Hu, Yu Wu and Yan Liu
Coatings 2023, 13(7), 1225; https://doi.org/10.3390/coatings13071225 - 8 Jul 2023
Viewed by 1052
Abstract
DZ22B alloy is commonly used as a blade material for aircraft engines and gas turbines, and its preparation process is an important factor affecting its performance. In the present work, a reliable numerical model is established through ProCAST numerical simulation and auxiliary experimental [...] Read more.
DZ22B alloy is commonly used as a blade material for aircraft engines and gas turbines, and its preparation process is an important factor affecting its performance. In the present work, a reliable numerical model is established through ProCAST numerical simulation and auxiliary experimental verification methods, based on which the effect of casting speed on the grain and dendrite growth of DZ22B superalloy blades is studied. The results indicate that increasing the pulling speed can reduce the spacing between secondary dendrites, which is beneficial for the growth of dendrites. Based on numerical simulation and experimental verification, it is suggested that the pulling rate of the directional solidification DZ22B superalloy blade should be 6-2 mm/min variable speed pulling to improve the production success rate. Full article
(This article belongs to the Special Issue Advances of Ceramic and Alloy Coatings)
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13 pages, 3247 KiB  
Article
Mechanical and Tribological Behaviors of Hot-Pressed SiC/SiCw-Y2O3 Ceramics with Different Y2O3 Contents
by Shaohua Zhang, Jinfang Wang, Meng Zhang, Longqi Ding, Huijun Chan, Xiyu Liu, Fengqing Wu, Zhibiao Tu, Ling Shao, Nengyong Ye, Sheng Dai, Liu Zhu and Shichang Chen
Coatings 2023, 13(5), 956; https://doi.org/10.3390/coatings13050956 - 19 May 2023
Cited by 2 | Viewed by 1537
Abstract
Sintering additives are commonly used to reduce the conditions required for densification in composite ceramics without compromising their performances simultaneously. Herein, SiC/SiCw-Y2O3 composite ceramics with 10 vol.% SiC whiskers (SiCw) and different Y2O3 [...] Read more.
Sintering additives are commonly used to reduce the conditions required for densification in composite ceramics without compromising their performances simultaneously. Herein, SiC/SiCw-Y2O3 composite ceramics with 10 vol.% SiC whiskers (SiCw) and different Y2O3 contents (0, 2.5, 5, 7.5, and 10 vol.%) were fabricated by hot-pressed sintering at 1800 °C, and the effects of Y2O3 content on the microstructure, mechanical properties, and tribological behaviors were investigated. It was found that the increased Y2O3 content can promote the densification of SiC/SiCw-Y2O3 composite ceramics, as evidenced by compact microstructure and increased relative density. The Vickers hardness, fracture toughness, and flexural strength also increased when Y2O3 content increased from 2.5 vol.% to 7.5 vol.%. However, excessive Y2O3 (10 vol.%) aggregated around SiC and SiCw weakens its positive effect. Furthermore, the Y2O3 additive also reduces the coefficient of friction (COF) of SiC/SiCw-Y2O3 composite ceramics, the higher the Y2O3 content, the lower the COF. The wear resistance of SiC/SiCw-Y2O3 composite ceramics is strongly affected by their microstructure and mechanical properties, and as-sintered SiC ceramic with 7.5 vol.% Y2O3 (Y075) shows the optimal wear resistance. The relative density, Vickers hardness, fracture toughness, and flexural strength of Y075 are 97.0%, 21.6 GPa, 7.7 MPa · m1/2, and 573.2 MPa, respectively, the specific wear rate of Y075 is 11.8% of that for its competitor with 2.5 vol.% Y2O3. Full article
(This article belongs to the Special Issue Advances of Ceramic and Alloy Coatings)
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9 pages, 2544 KiB  
Article
Interfacial Microstructure and Shear Behavior of the Copper/Q235 Steel/Copper Block Fabricated by Explosive Welding
by Jiansheng Li, Zuyuan Xu, Yu Zhao, Wei Jiang, Wenbo Qin, Qingzhong Mao, Yong Wei and Banglun Wang
Coatings 2023, 13(3), 600; https://doi.org/10.3390/coatings13030600 - 11 Mar 2023
Viewed by 1390
Abstract
A copper/Q235 steel/copper composite block with excellent bonding interfaces was prepared by explosive welding which was a promising technique to fabricate laminates. The microstructure and mechanical properties of the interfaces were investigated via the tensile-shear test, optical microscope (OM), X-ray diffraction (XRD), scanning [...] Read more.
A copper/Q235 steel/copper composite block with excellent bonding interfaces was prepared by explosive welding which was a promising technique to fabricate laminates. The microstructure and mechanical properties of the interfaces were investigated via the tensile-shear test, optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM), and electron back-scattered diffraction (EBSD). The results showed that the shear strength of the upper-interface and lower-interfaces of the welded copper/steel are higher than ~235 MPa and ~222 MPa, respectively. The specimens failed fully within the copper and not at the bonding interface. It was attributed to: (1) no cavities and cracks at the interface; (2) the interface formed a metallurgical bonding including numerous ultra-fine grains (UFGs) which can significantly improve the plastic deformation coordination at the interface and inhibit the generation of micro-cracks. Full article
(This article belongs to the Special Issue Advances of Ceramic and Alloy Coatings)
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13 pages, 9131 KiB  
Communication
Investigation of the Microstructures and Properties of B-Bearing High-Speed Alloy Steel
by Jingqiang Zhang, Penghui Yang and Rong Wang
Coatings 2022, 12(11), 1650; https://doi.org/10.3390/coatings12111650 - 31 Oct 2022
Cited by 2 | Viewed by 1298
Abstract
This work aims to research the influence of boron and quenching temperature on the microstructures and performances of boron-bearing high-speed alloy steel. The results showed that the hardness and wear resistance of boron-bearing high-speed alloy steel were improved after increasing the boron content. [...] Read more.
This work aims to research the influence of boron and quenching temperature on the microstructures and performances of boron-bearing high-speed alloy steel. The results showed that the hardness and wear resistance of boron-bearing high-speed alloy steel were improved after increasing the boron content. The volume fraction of boron-rich carbide gradually decreased, and the hardness increased significantly with the rise in quenching temperature. The highest comprehensive mechanical properties were obtained for samples quenched at 1040 °C. The TEM results showed the boron-rich carbide was M7(C, B)3 with an HCP structure, and the precipitated particles were M23(C, B)6 with an FCC structure after tempering. This work may help improve the wear resistance of materials in the field of surface coatings. Full article
(This article belongs to the Special Issue Advances of Ceramic and Alloy Coatings)
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12 pages, 3823 KiB  
Article
Microstructure and Corrosion Resistance of Two-Dimensional TiO2/MoS2 Hydrophobic Coating on AZ31B Magnesium Alloy
by Longjie Lai, Heng Wu, Guobing Mao, Zhengdao Li, Li Zhang and Qi Liu
Coatings 2022, 12(10), 1488; https://doi.org/10.3390/coatings12101488 - 6 Oct 2022
Cited by 8 | Viewed by 1816
Abstract
The corrosion resistance of magnesium alloys can be effectively improved by surface treatment. In this study, a hydrophobic two-dimensional (2D) TiO2/MoS2 nanocomposite coating was fabricated on AZ31B magnesium alloy by an electrophoretic deposition method. The corrosion resistance of the coating [...] Read more.
The corrosion resistance of magnesium alloys can be effectively improved by surface treatment. In this study, a hydrophobic two-dimensional (2D) TiO2/MoS2 nanocomposite coating was fabricated on AZ31B magnesium alloy by an electrophoretic deposition method. The corrosion resistance of the coating was evaluated using potentiodynamic polarization and electrochemical impedance spectroscopy analyses. After being modified by a silane coupling agent (KH570), the TiO2/MoS2 coating changed from hydrophilic to hydrophobic, and the static water contact angle increased to 131.53°. The corrosion experiment results indicated that the hydrophobic 2D TiO2/MoS2 coating had excellent anticorrosion performance (corrosion potential: Ecorr = −0.85 VAg/AgCl, and corrosion current density: Icorr = 6.73 × 10−8 A·cm−2). TiO2/MoS2 films have promising applications in magnesium alloy corrosion protection. Full article
(This article belongs to the Special Issue Advances of Ceramic and Alloy Coatings)
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10 pages, 4275 KiB  
Article
Effect of the Testing Temperature on the Impact Property of a Multilayered Soft–Hard Copper–Brass Block
by Tong Liu, Jiansheng Li, Kezhang Liu, Mengmeng Wang, Yu Zhao, Zhongchen Zhou, Yong Wei, Qi Yang, Ming Chen, Qingzhong Mao and Yufeng Sun
Coatings 2022, 12(9), 1236; https://doi.org/10.3390/coatings12091236 - 24 Aug 2022
Cited by 2 | Viewed by 2000
Abstract
The impact property is one of the most significant mechanical properties for metallic materials. In the current work, a soft–hard copper–brass block with a high yield strength of ~320 MPa and good uniform elongation of ~20% was prepared, and the effect of the [...] Read more.
The impact property is one of the most significant mechanical properties for metallic materials. In the current work, a soft–hard copper–brass block with a high yield strength of ~320 MPa and good uniform elongation of ~20% was prepared, and the effect of the testing temperature on its impact property was explored. The results showed that the impact energy was decreased with the increase in testing temperature. The impact energies at liquid nitrogen temperature (LNT), room temperature (RT), and 200 °C were 8.15 J, 7.39 J, and 7.04 J, respectively. The highest impact energy at LNT was attributed to the coordinated plastic deformation effects, which was indicated by the tiny dimples during the process of the delamination of soft–hard copper–brass interfaces. The high temperature of 200 °C can weaken the copper–brass interface and reduce the absorption of deformation energy, result in low impact energy. Full article
(This article belongs to the Special Issue Advances of Ceramic and Alloy Coatings)
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12 pages, 10364 KiB  
Article
Evaluation of Biocompatibility of 316 L Stainless Steels Coated with TiN, TiCN, and Ti-DLC Films
by Jia Lou, Beibei Ren, Jie Zhang, Hao He, Zonglong Gao and Wei Xu
Coatings 2022, 12(8), 1073; https://doi.org/10.3390/coatings12081073 - 29 Jul 2022
Cited by 6 | Viewed by 2023
Abstract
In this study, TiN, TiCN, and Ti-diamond-like carbon (Ti-DLC) films were coated on 316 L stainless steel (AISI 316 L) substrate surface by physical vapor deposition. The biocompatibility of the three films (TiN, TiCN, and Ti-DLC) and three metals (AISI 316 L, Ti, [...] Read more.
In this study, TiN, TiCN, and Ti-diamond-like carbon (Ti-DLC) films were coated on 316 L stainless steel (AISI 316 L) substrate surface by physical vapor deposition. The biocompatibility of the three films (TiN, TiCN, and Ti-DLC) and three metals (AISI 316 L, Ti, and Cu) was compared on the basis of the differences in the surface morphology, water contact angle measurements, CCK-8 experiment results, and flow cytometry test findings. The biocompatibility of the TiN and TiCN films is similar to that of AISI 316 L, which has good biocompatibility. However, the biocompatibility of the Ti-DLC films is relatively poor, which is mainly due to the inferior hydrophobicity and large amount of sp2 phases. The presence of TiC nanoclusters on the surface of the Ti-DLC film aggravates the inferior biocompatibility. Compared to the positive Cu control group, the Ti-DLC film had a higher cell proliferation rate and lower cell apoptosis rate. Although the Ti-DLC film inhibited cell survival to a certain extent, it did not show obvious cytotoxicity. TiN and TiCN displayed excellent performance in promoting cell proliferation and reducing cytotoxicity; thus, TiN and TiCN can be considered good orthodontic materials, whereas Ti-DLC films require further improvement. Full article
(This article belongs to the Special Issue Advances of Ceramic and Alloy Coatings)
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7 pages, 1986 KiB  
Article
Design of Ti-Zr-Ta Alloys with Low Elastic Modulus Reinforced by Spinodal Decomposition
by Rong Wu, Qionghua Yi, Shan Lei, Yilong Dai and Jianguo Lin
Coatings 2022, 12(6), 756; https://doi.org/10.3390/coatings12060756 - 31 May 2022
Cited by 5 | Viewed by 1916
Abstract
On the basis of the ternary phase diagram of Ti-Zr-Ta alloys and the d-electron orbital theory, the alloys with the nominal compositions of Ti-40Zr-20Ta (TZT1), Ti-35Zr-20Ta (TZT2) and Ti-30Zr-20Ta (TZT3) (in atom composition) were designed. The alloys were solution-treated (STed) at 1173 K [...] Read more.
On the basis of the ternary phase diagram of Ti-Zr-Ta alloys and the d-electron orbital theory, the alloys with the nominal compositions of Ti-40Zr-20Ta (TZT1), Ti-35Zr-20Ta (TZT2) and Ti-30Zr-20Ta (TZT3) (in atom composition) were designed. The alloys were solution-treated (STed) at 1173 K for 3 h, and then aged (Aed) at 973 K for 6 h. The microstructure and mechanical properties of the three alloys were characterized. The results show that the three alloys comprised β-equiaxed grains after solution treatment at 1173 K for 3 h, and the β phases separated into β12 phases by the spinodal decomposition in the alloys after being aged at 973 K for 6 h. The spinodal decomposition significantly promoted the yield strength of the alloys. For the TZT1 alloy, the yield strength increased from 1191 MPa (in the STed state) to 1580 MPa (in the Aed state), increasing by about 34%. The elastic moduli of the TZT1, TZT2 and TZT3 alloys after solution treatment at 1173 K were 75.0 GPa, 78.2 GPa and 85.8 GPa, respectively. After being aged at 973 K for 6 h, the elastic moduli of the three alloys increased to 81 GPa, 90 GPa and 92 GPa, respectively. Therefore, the spinodal decomposition can significantly promote the strength of the Ti-Zr-Ta alloys without a large increase in their elastic modulus. Full article
(This article belongs to the Special Issue Advances of Ceramic and Alloy Coatings)
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11 pages, 3242 KiB  
Article
Preparation of Ti-Al-Si Gradient Coating Based on Silicon Concentration Gradient and Added-Ce
by Zihan Wang, Faguo Li, Xiaoyuan Hu, Wei He, Zhan Liu and Yao Tan
Coatings 2022, 12(5), 683; https://doi.org/10.3390/coatings12050683 - 16 May 2022
Cited by 7 | Viewed by 2057
Abstract
Titanium and titanium alloys have excellent physical properties and process properties and are widely used in the aviation industry, but their high-temperature oxidation resistance is poor, and there is a thermal barrier temperature of 600 °C, which limits their application as high-temperature components. [...] Read more.
Titanium and titanium alloys have excellent physical properties and process properties and are widely used in the aviation industry, but their high-temperature oxidation resistance is poor, and there is a thermal barrier temperature of 600 °C, which limits their application as high-temperature components. The Self-generated Gradient Hot-dipping Infiltration (SGHDI) method is used to prepare the Ti-Al-Si gradient coating based on the silicon concentration with a compact Ti(Al,Si)3 phase layer, which can effectively improve the high-temperature oxidation resistance of the titanium alloy. Adding cerium can effectively inhibit the generation of the τ2: Ti(AlxSi1−x)2 phase within a certain hot infiltration time so as to form a continuous dense Al2O3 layer to further improve the oxidation resistance of the coating. Studies have found that multiple Ti-Al binary alloy phase layers are formed during the high-temperature oxidation process, which has the effect of isolating oxygen and crack growth, and effectively improving the high-temperature resistance of the coating oxidation performance. Full article
(This article belongs to the Special Issue Advances of Ceramic and Alloy Coatings)
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13 pages, 3927 KiB  
Article
Effect of Cryogenic Treatment on the Microstructure and Wear Resistance of 17Cr2Ni2MoVNb Carburizing Gear Steel
by Yongming Yan, Zixiang Luo, Ke Liu, Chen Zhang, Maoqiu Wang and Xinming Wang
Coatings 2022, 12(2), 281; https://doi.org/10.3390/coatings12020281 - 21 Feb 2022
Cited by 11 | Viewed by 2252
Abstract
Cryogenic treatment as a process that can effectively improve the performance of steel materials is widely used because of its simplicity and speed. This paper investigates the effects of different low temperature treatments on the microstructure and properties of 17Cr2Ni2MoVNb steel. The low [...] Read more.
Cryogenic treatment as a process that can effectively improve the performance of steel materials is widely used because of its simplicity and speed. This paper investigates the effects of different low temperature treatments on the microstructure and properties of 17Cr2Ni2MoVNb steel. The low temperature treatment range is divided into cryogenic treatment (CT-80), shallow cryogenic treatment (SCT-150) and deep cryogenic treatment (DCT-196), all with a duration of 1 h. The retained austenite content and the change in carbide volume fraction at 0.2 mm in the carburised layer are studied. The microhardness gradient of the carburised layer, as well as the friction coefficient and wear scar morphology at 0.2 mm, was investigated. The results show that the low temperature treatment is effective in reducing the retained austenite content and increasing the volume fraction of carbide. The lowest retained austenite content and highest carbide volume fraction were obtained for DCT-196 specimens at the same holding time. Due to the further transformation of martensite and the diffuse distribution of carbides, the microhardness and frictional wear properties of DCT-196 are optimal. Therefore, low temperature treatment can change the microstructure of the case layer of 17Cr2Ni2MoVNb steel and effectively improve the mechanical properties of materials. Full article
(This article belongs to the Special Issue Advances of Ceramic and Alloy Coatings)
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15 pages, 4139 KiB  
Article
Phase Stability and Mechanical Properties of the Monoclinic, Monoclinic-Prime and Tetragonal REMO4 (M = Ta, Nb) from First-Principles Calculations
by Wenhui Xiao, Ying Yang, Zhipeng Pi and Fan Zhang
Coatings 2022, 12(1), 73; https://doi.org/10.3390/coatings12010073 - 8 Jan 2022
Cited by 13 | Viewed by 2508
Abstract
YTaO4 and the relevant modification are considered to be a promising new thermal barrier coating. In this article, phase stability and mechanical properties of the monoclinic (M), monoclinic-prime (M′), and tetragonal (T) REMO4 (M = Ta, Nb) are systematically investigated from [...] Read more.
YTaO4 and the relevant modification are considered to be a promising new thermal barrier coating. In this article, phase stability and mechanical properties of the monoclinic (M), monoclinic-prime (M′), and tetragonal (T) REMO4 (M = Ta, Nb) are systematically investigated from first-principles calculations method based on density functional theory (DFT). Our calculations show that M′-RETaO4 is the thermodynamically stable phase at low temperatures, but the stable phase is a monoclinic structure for RENbO4. Moreover, the calculated relative energies between M (or M′) and T phases are inversely proportional to the ionic radius of rare earth elements. It means that the phase transformation temperature of M′→T or M→T could decrease along with the increasing ionic radius of RE3+, which is consistent with the experimental results. Besides, our calculations exhibit that adding Nb into the M′-RETaO4 phase could induce phase transformation temperature of M′→M. Elastic coefficient is attained by means of the strain-energy method. According to the Voigt–Reuss–Hill approximation method, bulk modulus, shear modulus, Young’s modulus, and Poisson’s ratio of T, M, and M’ phases are obtained. The B/G criterion proposed by Pugh theory exhibits that T, M, and M’ phases are all ductile. The hardness of REMO4 (M = Ta, Nb) phases are predicted based on semi-empirical equations, which is consistent with the experimental data. Finally, the anisotropic mechanical properties of the REMO4 materials have been analyzed. The emerging understanding provides theoretical guidance for the related materials development. Full article
(This article belongs to the Special Issue Advances of Ceramic and Alloy Coatings)
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13 pages, 4117 KiB  
Article
Comparative Investigation on Corrosion Resistance of Stainless Steels Coated with Titanium Nitride, Nitrogen Titanium Carbide and Titanium-Diamond-like Carbon Films
by Jia Lou, Zonglong Gao, Jie Zhang, Hao He and Xinming Wang
Coatings 2021, 11(12), 1543; https://doi.org/10.3390/coatings11121543 - 15 Dec 2021
Cited by 15 | Viewed by 3638
Abstract
In this study, the corrosion resistance of titanium nitride (TiN), nitrogen titanium carbide (TiCN) and titanium-diamond-like carbon (Ti-DLC) films deposited on 316L stainless steel (SS) were compared via differences in the surface and section-cross morphologies, open circuit potential tests, electrochemical impedance spectroscopy and [...] Read more.
In this study, the corrosion resistance of titanium nitride (TiN), nitrogen titanium carbide (TiCN) and titanium-diamond-like carbon (Ti-DLC) films deposited on 316L stainless steel (SS) were compared via differences in the surface and section-cross morphologies, open circuit potential tests, electrochemical impedance spectroscopy and potentiometric tests. The corrosion resistance of the TiCN and Ti-DLC films significantly improved because of the titanium carbide (TiC) crystals that obstruct the corrosive species penetrating the as-deposited film in the electrolyte atmosphere. TiN exhibited the lowest corrosion resistance because of its low thickness and high volume of defects. The Ti-DLC film showed the lowest corrosion current density (approximately 4.577 μA/cm2) and thickness reduction (approximately 0.12 μm) in different electrolytes, particularly those with high Cl and H+ concentrations, proving to be the most suitable corrosion protection material for 316L SS substrates. Full article
(This article belongs to the Special Issue Advances of Ceramic and Alloy Coatings)
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