一种铬基高温合金的组织及其时效处理细化  

Microstructure of a Chromium-Based Superalloy and Its Refinement by Aging

作　　者：郝军明[1] 李殿国[2] 周浪[1] 

机构地区：[1]南昌大学材料科学与工程学院,江西南昌330047 [2]北京钢铁研究总院高温材料研究所,北京100083

出　　处：《南昌大学学报（工科版）》2004年第2期10-13,共4页Journal of Nanchang University(Engineering & Technology)

基　　金：国家自然科学基金资助项目(59701012)

摘　　要：铬基合金耐热腐蚀性强、比重小、熔点高,是一种极有前途的轻比重高温材料.本文根据Cr-Ni相图的特点,对一种含Ni40%wt的铬基高温合金的组织及其高温时效处理细化进行了研究.合金在1300℃保温4h水冷固溶处理后获得了一种富Ni相与富Cr相呈分立晶粒的过饱和双相固溶组织,其后分别在1080℃和1000℃4h时效.采用金相显微镜和扫描电镜配合特征X射线能谱分析合金显微组织.结果表明合金在职1000℃时效条件下能获得一种由高密度微米级析出相和被分割为微米级基体相组成的复相组织.试验观察还显示:固溶态初始两相晶粒之间在高温时效中发生过饱和溶质互扩散,消耗各自过饱和度,使析出相量减少,并造成两相晶界上无析出带的存在.Chromium-based alloy has a great potential in high temperature application,for its hot corrosion resistance,low density and high melting point.On basis of the feature of Cr-Ni phase diagram,we have carried out a study of the microstructure of a Cr-base alloy containing 40%wt Cr,and its refinement by means of aging treatment.After a solid solution treatment of 1 300 ℃/4 hours followed by water quench,a structure of (supersaturated) dual phases is obtained,in which the Cr-rich phase and the Ni-rich phase appear in form of separated grains.The alloy is then aged at 1 080 ℃ and 1 000 ℃ respectively for 4 hours.A composite structure with high density of micrometer scale precipitates separating the matrix into micrometer scale domains is (obtained) with the 1 000 ℃ aging process.The present work also shows that inter-diffusion between the original grains of different phases takes place in aging,and leads to consumption of the supersaturation in each phase,(resulting) in reduction of the precipitates.

关 键 词：铬基合金 沉淀 时效 

分 类 号：TG132.32[一般工业技术—材料科学与工程] TG156.92[金属学及工艺—合金]