(西北工業(yè)大學(xué) 凝固技術(shù)國(guó)家重點(diǎn)實(shí)驗(yàn)室，西安 710072)
摘 要: 采用擴(kuò)散共滲方法在Nb-Ti-Si-Cr基超高溫合金表面制備Zr-Y改性的硅化物滲層，對(duì)比研究基體合金和共滲層在室溫和800 °C與SiC球?qū)δr(shí)的摩擦磨損性能。所制備的Zr-Y改性硅化物滲層主要由較厚的(Nb, X)Si2外層和較薄的(Ti, Nb)5Si4內(nèi)層組成。共滲層的顯微硬度明顯高于基體合金。基體合金和共滲層在常溫和800 °C時(shí)的磨損率均隨摩擦載荷的增加而增加，但在相同的摩擦條件下，共滲層的磨損率明顯低于基體合金。Zr-Y改性硅化物滲層在室溫和800 °C時(shí)的磨損抗力均優(yōu)于基體合金，能夠?yàn)榛w合金提供良好的保護(hù)。
關(guān)鍵字: Nb-Ti-Si-Cr基合金；Zr-Y改性硅化物滲層；摩擦磨損；磨損機(jī)制
（State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China）
Abstract: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 °C 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 °C in air.
Key words: Nb-Ti-Si-Cr based alloy; Zr-Y modified silicide coating; friction and wear; wear mechanism
