Effect of alloying elements on microstructure evolution and wear mechanism of MCrAlX-based coatings at 800 °C

• Published in: Surface & coatings technology 2023-03, Vol.456, p.129266, Article 129266
• Main Authors: Hao, Enkang, Chen, Jie, Liu, Guang, Cui, Lang, Jia, Li, Wei, Liankun, Ma, Bing, An, Yulong
• Format: Article
• Language: English
• Subjects: Alloying elements; High-temperature friction and wear; MCrAlX coatings; Mechanical properties; Microstructure
• ISSN: 0257-8972
• DOI: 10.1016/j.surfcoat.2023.129266

MCrAlX coatings (M = Ni, Co or NiCo; X = Y, Hf, Ta and Si, etc.) have an excellent oxidation resistant, but in which the various alloying elements will lead to the difference in evolution mechanism of microstructure at high temperature, and thus affects its friction and wear mechanism. Therefore, NiCrAlY, NiCoCrAlYHfSi and NiCoCrAlYTa coatings are deposited by high velocity oxy-fuel (HVOF) spraying technology in this work. The tribological properties of three kinds coatings at 800 °C are mainly investigated. The emphasis is placed at the influences of alloying elements on evolution mechanism of microstructure as well as mechanical and tribological properties of three coatings. All the coatings are dense and uniform, and their phases are roughly same. However, the different alloying elements lead to the different mechanical properties of coatings. Meanwhile, with the increase of hardness, the wear rate and friction coefficient of the coatings decrease obviously. Especially, the friction coefficient and wear rate of NiCoCrAlYTa coating are significantly lower than those of the other coatings. This phenomenon is mainly attributed to the transformation of worn damage pattern of the coating and the generation of continuous glaze layer at the friction interface. In conclusion, this work could be considered as a guidance to expand the applications of MCrAlX-based coating in modern industries. [Display omitted] •The performance of MCrAlX-based coatings is different with varying alloy elements.•The NiCoCrAlYTa coating exhibits the better mechanical and tribological properties.•The wear mechanism of coatings is related to the formation and spreading of glaze layer.•The glaze layer is composed of mixed oxides, layer-like spinel and amorphous phase.