MAX phase forming mechanism of M-Al-C(M=Ti,V,Cr)coatings:In-situ X-ray diffraction and first-principle calculations  

作　　者：Jianghuai Yuan Zhenyu Wang Guanshui Ma Xiaojing Bai Yong Li Xiaoying Cheng Peiling Ke Aiying Wang 

机构地区：[1]Key Laboratory of Marine Materials and Related Technologies,Zhejiang Key Laboratory of Marine Materials and Protective Technologies,Ningbo Institute of Materials Technology and Engineering,Chinese Academy of Sciences,Ningbo 315201,China [2]School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China [3]School of Materials Science and Engineering,Anyang Institute of Technology,Anyang 455000,China [4]Analytical Center,Ningbo Institute of Materials Technology and Engineering,Chinese Academy of Sciences,Ningbo 315201,China

出　　处：《Journal of Materials Science & Technology》2023年第12期140-152,共13页材料科学技术（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (Nos.52025014,52171090,52101109,U22A20111).

摘　　要：The interesting hybrid properties of ceramics and metals induced by unique nano-laminated structures make the M_(n+1)AX n(MAX)phase attractive as a potential protective coating for vital structural compo-nents in harsh systems.However,an extremely narrow phase-forming region makes it difficult to prepare MAX phase coatings with high purity,which is required to obtain coatings with high-temperature anti-oxidation capabilities.This work describes the dependence of the phase evolution in deposited M-Al-C(M=Ti,V,Cr)coatings as a function on temperature using in-situ X-ray diffraction analysis.Compared to V_(2)AlC and Cr_(2)AlC MAX phase coatings,the Ti_(2)AlC coating displayed a higher phase-forming tempera-ture accompanied by a lack of any intermediate phases before the appearance of the Ti_(2)AlC MAX phase.The results of the first-principle calculations correlated with the experience in which Ti_(2)AlC exhibited the largest formation energy and density of states.The effect of the phase compositions of these three MAX phase coatings on mechanical properties were also investigated using ex-situ Vickers and nano-indenter tests,demonstrating the improved mechanical properties with good stability at high temperatures.These findings provide a deeper understanding of the phase-forming mechanism of MAX phase coatings to guide the preparation of high-purity MAX phase coatings and the optimization of MAX phase coatings with expected intermediate phases such as Cr_(2)C,V_(2)C etc.,as well as their application as protective coat-ings in temperature-related harsh environments.

关 键 词：MAX phase coating Phase-formation mechanism In-situ X-ray diffraction First-principle calculations Mechanical properties 

分 类 号：TG146.23[一般工业技术—材料科学与工程]