等离子表面Cr-Si合金化改善TiAl基合金高温性能的研究  

Improving TiAl-Based Alloy High Temperature Properties by Plasma Surface Cr-Si Alloying

作　　者：李亚非 张平则[1] 许浩 

机构地区：[1]南京航空航天大学材料科学与技术学院,南京211106 [2]中航工业中南传动机械厂军品分厂,长沙410200

出　　处：《航空材料学报》2011年第6期43-49,共7页Journal of Aeronautical Materials

基　　金：江苏省自然科学基金资助项目(BK2005128)

摘　　要：利用等离子表面合金化技术,在TiAl基合金表面实现了Cr-Si二元共渗。使用扫描电镜(SEM)、能谱(EDS)和X衍射仪(XRD)检测了合金渗层的形貌、合金元素含量与相组成,并研究了合金化处理对TiAl基合金高温抗氧化性能与高温耐磨性能的改善效果。结果显示,合金渗层组成相为Cr3Si及Laves相TiCr2,过渡层物相主要为Al8Cr5与Al3Ti,合金层内Cr,Si元素含量呈梯度分布。经高温氧化,合金渗层表层形成致密CrO2,内层形成连续Al2O3阻隔层,其氧化动力学曲线呈现典型的抛物线型。较之原始TiAl基合金摩擦学特性,Cr-Si合金渗层的磨粒磨损程度降低极大,氧化磨损受到抑制,其相对耐磨性能提高了17.3倍。Plasma alloying of Cr-Si on TiAl-based alloy was achieved by using Double Glow Plasma Surface alloying technology.Morphology,content of elements and phase composition were characterized by means of SEM,EDS and XRD.High temperature oxidation resistance and wear resistance of alloyed layer were also investigated.The results show that the phase in alloyed layer is composed of Cr3Si and Laves phase TiCr2.The phases in transition layer are Al8Cr5 and Al3Ti.The concentration of Cr and Si displays gradient distribution.Dense CrO2 and continuous protective Al2O3 film were formed in the process of oxidation.The curve of oxidation kinetics was parabolic.The extent of abrasive wear and oxidation wear decreased dramatically due to the plasma alloying process.Relative wear resistance of alloying layer had enhanced 17.3 times.

关 键 词：TIAL基合金 等离子表面合金化 高温抗氧化性能 高温耐磨性能 

分 类 号：TG156.8[金属学及工艺—热处理] TG174.445[金属学及工艺—金属学]