热处理对B2相区等温锻造Ti-22Al-25Nb合金组织和性能的影响  

Effect of Heat Treatment on Microstructure and Mechanical Properties of Isothermally Forged Ti-22Al-25Nb Alloy at B2-phase Region

作　　者：董志国 李冬[2] 曾卫东[2] 王伟[2] 梁晓波[3] Dong Zhiguo;Li Dong;Zeng Weidong;Wang Wei;Liang Xiaobo(AECC Shenyang Engine Research Institute,Shenyang 110015,China;State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi’an 710072,China;Central Iron and Steel Research Institute,Beijing 100081,China)

机构地区：[1]中国航发沈阳发动机研究所,辽宁沈阳110015 [2]西北工业大学凝固技术国家重点实验室,陕西西安710072 [3]钢铁研究总院,北京100081

出　　处：《钛工业进展》2018年第3期22-25,共4页Titanium Industry Progress

基　　金：凝固技术国家重点实验室自主研究课题资助项目(153-ZH-2016)

摘　　要：研究了B2单相区等温锻造Ti-22Al-25Nb(原子分数)合金经不同固溶加时效热处理工艺处理后,其显微组织的演变和力学性能的变化。研究结果表明,随着固溶温度的升高,Ti-22Al-25Nb合金组织中一次板条状O相变短变粗,体积分数减小,有球化的趋势,在随后的时效过程中会析出更多的次生针状板条O相;拉伸强度也随固溶温度升高而增加,塑性略微提高,断裂主要以沿B2晶粒的解理面解理断裂或准解理断裂为主,呈现许多近似层状的解理小刻面,其微观形貌为微孔状的韧窝。The microstructure evolution and mechanical properties of isothermally forged Ti-22Al-25Nb(at.%)alloy at B2-phase region during two different heat treatments were investigated.The results indicate that lamellar O phase becomes shorter and coarser,the volume fraction decreases,and tends to be spheroidized with the increasing of solution temperature.And during the subsequent aging process,more secondary O phase is precipitated.The mechanical properties of the Ti-22Al-25Nb alloy show that the tensile strength and ductility increase with the increasing of solution temperature.The fracture mode mainly consistes of cleavage fracture or quasi-cleavage fracture along B2 grain,and the fracture surface presents a lot of approximate layered cleavage surface,whose microstructure is the micro-porous dimples.

关 键 词：TI2ALNB基合金 等温锻造 热处理 显微组织 拉伸性能 

分 类 号：TG146.23[一般工业技术—材料科学与工程]