高温均匀化及时效处理对Nb-Ti-Si基超高温合金组织的影响  

Effects of High-Temperature Homogenizing and Aging Treatments on the Microstructure of Nb-Ti-Si Based Ultrahigh Temperature Alloy

作　　者：郭海生[1] 郭喜平[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《稀有金属材料与工程》2008年第9期1601-1605,共5页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(50671081);西北工业大学博士论文创新基金(CX200605)资助

摘　　要：采用真空非自耗电弧熔炼法制备Nb-Ti-Si基超高温合金的母合金锭,分别于1300、1400、1500和1600℃保温50h,对其进行均匀化处理,然后于1100℃保温50h进行时效处理。结果表明:热处理后的组织主要由Nbss和(Nb、x)5Si3(x代表Ti、Cr和Hf元素)组成,经1600℃、50h和1600℃、50h+1100℃、50h热处理后的组织中还出现HfO2。随着热处理温度的升高,多边形和板条状大块硅化物逐渐溶解或破碎成小块硅化物,残留的具有典型层片状或团状形貌的共晶组织的含量逐渐减少。1500℃、50h+1100℃、50h是Nb-Ti-Si基超高温合金比较合理的热处理工艺。The master alloy ingot of Nb-Ti-Si based ultrahigh temperature alloy was prepared by vacuum nonconsumable arc melting. The coupons were homogenized at 1300, 1400, 1500 and 1600 ℃ for 50 hours respectively, and then aged at 1100 ℃ for 50 hours. The heat-treated microstructures were still composed of Nbss and （Nb, x）5Si3 （x represents Ti, Hf and Cr elements）. But after the heat treatments both at 1600 ℃, 50 h and 1600 ℃, 50 h＋1100 ℃, 50 h, HfO2 was found in the mucrostructure. With the increase of heat treatment temperatures, polygonal and plate-like big （Nb, x）5Si3is desolved gradually or broken into small ones, and the amount of retained typical lamellar or rod eutectic colonies reduced gradually. 1500 ℃, 50 h＋1100℃, 50 h is an optimum heat treatment process for Nb-Ti-Si based ultrahigh temperature alloy.

关 键 词：均匀化处理 时效处理 Nb-Ti—Si基超高温合金 组织变化 

分 类 号：TG166[金属学及工艺—热处理]