低铬合金化TiAl的高温氧化  

High Temperature Oxidation of Ti Al Cr Alloys

作　　者：曲恒磊[1] 周廉[1] 魏海荣[2] 赵永庆 

机构地区：[1]西北有色金属研究总院,西安710016 [2]东北大学,沈阳110006

出　　处：《稀有金属》2001年第2期81-85,共5页Chinese Journal of Rare Metals

基　　金：国家自然科学基金资助项目

摘　　要：用热重分析法 (TGA)研究了Ti 48Al ( 0～ 4)Cr合金在各种条件下 10 0h内的高温氧化行为。氧化增重ΔM随TiAl中铬元素添加量的增大而先升后降。Ti 48Al 1Cr在各种条件下均表现为耐氧化性最差 ,原因在于适量铬固溶于TiAl基体中 ,有助于氧化时钛离子的扩散 ;铬含量进一步增高时 ,将有可能引入第三相Ti2 CrAl( β2 ) ,易形成较具保护性的Cr2 O3 ,从而抑制氧化反应速度。一般地 ,低铬合金化后TiAl的耐氧化性下降 ,但氧化膜粘附性、致密性均有明显提高。TiAl表面氧化物呈分层结构 ,主相为TiO2 与Al2 O3 。Oxidation behaviours of Ti 48Al (0,1,4) Cr alloys under various conditions were studied by TGA method. The results show that mass gain ΔM increases first and then decreases at last with increase of chromium addition. The reason why Ti 48Al 1Cr alloy exhibits poor oxidation resistance lies in that small amount of Cr solubilized in TiAl matrix promotes the diffusion of Ti 4+ ions, while more Cr addition induces the formation of a third phase Ti 2CrAl( β 2), which facilitates the growth of protective Cr 2O 3, and thus declines the corrosion speed of TiAl. However, Cr improves the adhesivity and compatibility of oxide, which is mainly consisted of TiO 2 and Al 2O 3.

关 键 词：TiAl-Cr 氧化增重 Ti2GrAl 热重分析法 高温氧化 

分 类 号：TG146.2[一般工业技术—材料科学与工程] TG172.82[金属学及工艺—金属材料]