Friction and wear behaviors of Nb-Ti-Si-Cr based ultrahigh temperature alloy and its Zr-Y jointly modified silicide coatings  

Nb-Ti-Si-Cr基超高温合金及其表面Zr-Y联合改性硅化物渗层的摩擦磨损性能（英文）

作　　者：李轩[1] 郭喜平[1] 乔彦强[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,西安710072

出　　处：《Transactions of Nonferrous Metals Society of China》2016年第7期1892-1901,共10页中国有色金属学报（英文版）

基　　金：Projects(51371145,51431003,U1435201,51401166)supported by the National Natural Science Foundation of China;Project(B080401)supported by the Programme of Introducing Talents of Discipline to Universities,China

摘　　要：Zr-Y jointly modified silicide coatings were prepared on an Nb-Ti-Si-Cr based ultrahigh temperature alloy by pack cementation process. The wear behaviors of both the base alloy and coatings were comparatively studied at room temperature and 800 ℃ using SiC balls as the counterpart. The Zr-Y jointly modified silicide coating is mainly composed of a thick （Nb,X）Si2 outer layer and a thin （Ti,Nb）5Si4 inner layer. The coatings possess much higher microhardness than the base alloy. The wear rates of both the base alloy and coatings increase with increasing the sliding loads. However, the coatings have much lower wear rates than the base alloy under the same sliding conditions. The coatings have superior anti-friction property, and can provide effective protection for the base alloy at both room temperature and 800 ℃ in air.采用扩散共渗方法在Nb-Ti-Si-Cr基超高温合金表面制备Zr-Y改性的硅化物渗层,对比研究基体合金和共渗层在室温和800°C与SiC球对磨时的摩擦磨损性能。所制备的Zr-Y改性硅化物渗层主要由较厚的(Nb,X)Si_2外层和较薄的(Ti,Nb)_5Si_4内层组成。共渗层的显微硬度明显高于基体合金。基体合金和共渗层在常温和800°C时的磨损率均随摩擦载荷的增加而增加,但在相同的摩擦条件下,共渗层的磨损率明显低于基体合金。Zr-Y改性硅化物渗层在室温和800°C时的磨损抗力均优于基体合金,能够为基体合金提供良好的保护。

关 键 词：Nb-Ti-Si-Cr based alloy Zr-Y modified silicide coating friction and wear wear mechanism 

分 类 号：TG174.4[金属学及工艺—金属表面处理]