固溶和时效处理对粗晶Ti-22Al-25Nb合金显微组织的影响  

Effects of Solid Solution and Aging Treatment on Microstructure of Coarse Grain Ti-22Al-25Nb Alloy

作　　者：周伟 姚泽坤[2] 马震 ZHOU Wei1, YAO Zekun2, MA Zhen1(1. Xi＇an ASN Technology Group Co., Ltd., Xi＇an 710065, China; 2. School of Materials, Northwestern Polytechnical University, Xi＇an 710072, Chin)

机构地区：[1]西安爱生技术集团公司.陕西西安710065 [2]西北工业大学材料学院,陕西西安710072

出　　处：《热加工工艺》2018年第14期208-212,共5页Hot Working Technology

基　　金：国家自然科学基金项目(51175431)

摘　　要：通过一系列固溶和时效热处理试验,研究了不同温度和时间对粗晶Ti-22Al-25Nb合金组织显微组织演变的影响。结果表明：在（O＋B2）相温度区间进行固溶时,随着温度的升高,合金的O相含量逐渐增加,尺寸逐渐变大,在外观形态上由针状逐渐长大为球状;在（O＋α2＋B2）和（α2＋B2）相温度区间进行固溶时,随温度升高合金表现为α2相颗粒的增多和长大。合金在730℃进行短时时效时,主要表现为α2相的析出和初生O相的形成,时效时间越长,α2相和O相的长大越明显;在870℃进行短时时效时,表现为晶界α2相的聚集和晶粒内部条状O相的形成,随着时效时间的延长,α2＋β→O的转变程度增加,α2相含量出现明显的降低。The effects of different temperature and time on microstructure evolution of coarse Ti-22Al-25Nb alloy were studied by a series of solution and aging heat treatment tests.The results show that,the content of O phase increases with the increase of temperature when the solution is carried out in the temperature range of（O＋B2）phase.The size gradually becomes larger,and the appearance grows from needle to ball.When the solution is carried out in the temperature range of（O＋α2＋B2）and（α2＋B2）phase,the increase ofα2phase particles content and the growth ofα2phase particles are observed with the increase of temperature.When the alloy is aged at 730℃for short time,the precipitation ofα2phase and the formation of primary O phase are the main characteristics of the alloy.The longer the aging time is,the more obvious the growth ofα2phase and O phase is.Aging at 870℃for short time,α2phase aggregation in grain boundary and the formation of stripe O phase in grains are observed.With the increase of aging time,the transformation degree ofα2＋β→O increases,and the content ofα2phase decreases obviously.

关 键 词：TI-22AL-25NB合金 显微组织 固溶 时效 

分 类 号：TG156.9[金属学及工艺—热处理] TG146.23[金属学及工艺—金属学]