论文部分内容阅读
采用先磁控溅射Zr膜,再Si-Y扩散共渗的方法,在新型Nb-Ti-Si-Cr基超高温合金表面制备了Zr Si2-Nb Si2复合渗层,分析了渗层的显微组织及形成机制,并研究了其在1250℃的恒温氧化行为.结果表明,1150,1250和1350℃下Si-Y共渗4 h所制备的渗层具有相似的显微组织,均主要由Zr Si2外层,(Nb,X)Si2(X=Ti,Cr,Zr和Hf)中间层和(Ti,Nb)5Si4内层组成.恒温氧化实验结果表明,所制备的渗层具有优异的抗高温氧化性能.氧化时渗层表面形成了由Si O2,Ti O2,Zr Si O4和Cr2O3混合组成的致密氧化膜,能够在1250℃空气中保护基体合金至少100 h不被氧化.
Zr Si2-Nb Si2 composite layer was prepared on the surface of a novel Nb-Ti-Si-Cr based superalloy by magnetron sputtering of Zr film followed by Si-Y diffusion co-infiltration. The microstructure and the formation mechanism were investigated and the results of the isothermal oxidation at 1250 ℃ showed that the diffusion layer prepared by Si-Y permeation at 1150, 1250 and 1350 ℃ for 4 h had similar microstructure, (Si, Nb, X) Si2 (X = Ti, Cr, Zr and Hf) and the inner layer of (Ti, Nb) 5Si4.The results of isothermal oxidation experiment show that the prepared layer has excellent resistance High temperature oxidation performance. The oxide layer formed on the surface of the oxide layer by the Si O2, Ti O2, Zr Si O4 and Cr2O3 mixed compact oxide film can be 1250 ℃ in the air to protect the base alloy is not oxidized at least 100 h.