热处理对铸造Ti2AlNb合金组织和力学性能的影响  

Effect of Heat Treatment on Microstructure and Properties of Cast Ti-22Al-25Nb Alloy

作　　者：骆晨 张寅[3] 王新英 梁晓波 张建伟[1,2] Luo Chen;Zhang Yin;Wang Xinying;Liang Xiaobo;Zhang Jianwei(Gaona Areo Materials,Beijing 100081;Beijing Key Laboratory of Advanced High Temperature Materials,Central Iron and Steel Research Institute,Beijing 100081;Capital Aerospace Machinery Co.,Ltd.,Beijing 100076)

机构地区：[1]北京钢研高纳科技股份有限公司,北京100081 [2]钢铁研究总院高温合金新材料北京市重点实验室,北京100081 [3]首都航天机械有限公司,北京100076

出　　处：《航天制造技术》2020年第2期18-20,共3页Aerospace Manufacturing Technology

摘　　要：研究了不同热处理制度对铸造Ti-22Al-25Nb(at%)合金组织和力学性能的影响,结果表明:合金经热等静压后的微观组织由初生粗板条状O相和B2相基体组成,其室温抗拉强度达到1006MPa,塑性约为1.0%。经980℃固溶处理,铸造组织中的O相板条宽度有所增加,其拉伸强度下降接近900MPa,塑性提高到3%。铸件在1080℃固溶处理+850℃时效处理后,组织中的初生粗板条发生溶解,在B2相基体中析出细的O相板条,该种组织的室温拉伸强度超过1000MPa,但其塑性明显下降,不足1%,当时效温度提高至900℃,二次O相板条粗化,组织强度下降约100MPa,塑性没有明显改善。Microstructure evolution of the cast Ti-22Al-25Nb(at%)alloy during different heat treatments was investigated,while the tensile properties of the alloy with different heat treatments were tested.It is found that the cast alloy microstructure after hot isostatic pressing is composed of O phase laths and B2 matrix,which of the room tensile strength come to 1006MPa,the room ductility is about 1%.During 980℃ solution treatment,the width of O phase laths increases,and the tensile strength decreases to 900MPa,the ductility increases to 3%.After 1080℃ solution plus 850℃ aging treatment,the original O phase laths in the microstructure solves and the fine O phase lamellae precipitates from B2 matrix,the tensile strength of the microstructure is above 1000MPa,but the ductility decreases obviously,which is less than 1%.When the aging temperature raises 900℃,the second O phase lamellae croses,and the tensile strength decreases about 100MPa,the ductility increases a little.

关 键 词：铸造Ti2AlNb合金 热处理 拉伸性能 

分 类 号：TG166.5[金属学及工艺—热处理] TG292[金属学及工艺—金属学] TG146.23[一般工业技术—材料科学与工程]