等离子熔覆多元镍基涂层-基体的力学性能研究

Mechanical Property of Plasma Cladded Multivariate Nickel-based Coating and Substrate

目的在FV520B不锈钢基体上,采用等离子熔覆技术制备多元镍基涂层,研究不同成分配比涂层-基体协同作用下的力学性能。方法通过扫描电子显微镜分析涂层的表面及界面形貌,并对涂层-基体进行了拉伸及高温压缩性能测试,得到各涂层的抗拉强度及高温变形抗力,对比分析组织、相分布特征及涂层成分对涂层-基体系统力学性能的影响。结果等离子熔覆涂层组织致密,界面处呈现良好的冶金结合,这种结合方式可提高涂层-基体的综合力学性能;涂层-基体协同作用可显著提高材料的抗拉强度及变形抗力,且涂层的成分、组织及相分布特征是影响涂层-基体协同形变行为的关键因素。其中,Ni60+20%Ti涂层材料的抗拉伸性能最好,抗拉强度高达921 MPa,较基体材料提高了19.6%。Ni60+30%Ti+10%WC涂层-基体的高温力学性能最好,高温变形抗力达687.87 MPa。结论等离子熔覆多元镍基涂层使基体材料的抗拉强度有所提高,且高温变形抗力提高显著。

The work aims to study mechanical property under synergistic effect of coating-substrate in different composition pro- portion by preparing multi-element nickel-based coatingon FV520B stainless steel substrate by adopting plasma cladding technology. Surface and interface morphology of the coatingswere observed byusing scanning electron microscope （SEM）, tensile and high temper- ature compression property of the coating-substmte were tested. Tensile strength and high temperature deformation resistance of each coating were obtained. Influences of structure, phase distribution characteristics and coating composition on mechanical properties of the coating-substrate system were analyzed. Plasma cladded coatings featured in dense microstructure and good metallurgical bonding on interface, the bonding mode could improve comprehensive mechanical property of the coating-substrate; synergistic effectof the coaling-substrate could improve tensile strength and deformation resistance significantly, and composition, structure and phase distribu- tion characteristics of the coatingswere key factors influencing synergistic deformation behavior of the coating-substrate. The coating Ni60＋20%Ti exhibited the best tensile strength, which was up to 921 MPa, 19.6% higher than that of substrate material. The coating Ni60＋30%Ti＋ 10%WC exhibited the best high temperature mechanical properties, the high temperature deformation resistance was up to 687.87 MPa. Tensile strength of the plasma claddedmulti-element nickel-based coating on the substrate improves, and the high tem- perature deformation resistance improves significantly.