热处理工艺对Ti_(2)AlNb合金锻件显微组织和拉伸性能的影响  

Effects of Heat Treatment Process on Microstructure and Tensile Properties of Ti_(2)AlNb Alloy Forging

作　　者：邢丕臣 师俊东 马雄 张熹雯[2,3] 梁晓波 张建伟[2,3] XING Picheng;SHI Jundong;MA Xiong;ZHANG Xiwen;LIANG Xiaobo;ZHANG Jianwei(AECC Shenyang Engine Research Institute,Shenyang 110015,China;Gaona Aero Material Co.,Ltd.,Beijing 100081,China;High Temperature Materials Research Institute,Central Iron&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]北京钢研高纳科技股份有限公司,北京100081 [3]钢铁研究总院高温材料研究所,北京100081

出　　处：《热加工工艺》2022年第24期119-124,共6页Hot Working Technology

基　　金：国家科技重大专项项目(2017-Ⅵ-0004-0074)。

摘　　要：以Ti-22Al-25Nb合金某机匣用环形锻件为研究对象,研究了固溶温度和固溶时间对该锻件微观组织、室温和650℃高温拉伸性能的影响,揭示了显微组织与拉伸性能之间的关系。结果表明:固溶时效处理后形成了以等轴α2颗粒、一次板条O相和二次针状O相为主的双态组织。固溶时间的延长对微观组织影响较小。固溶温度的升高一方面会显著降低一次板条O相的含量,另一方面会显著增加时效过程中析出的二次针状O相含量。二次针状O相含量的增加降低了位错运动的平均自由程,增加析出强化作用,从而导致合金的室温强度和高温强度增加,反之塑性下降。The effects of solution temperature and solution time on the microstructure and tensile properties at room temperature and 650 ℃ high temperature stretching for a case ring forging of Ti-22Al-25Nb alloy were studied. The relationships between the microstructure and tensile properties were also revealed. The results show that the bimodal microstructure is composed of the equiaxed α2particles, primary lath O phase and secondary acicular O phase. The prolongation of solution time has little effect on the microstructure. On the one hand, the increase of solution temperature will significantly reduce the content of primary lath O phase, and on the O ther hand, it will significantly increase the content of secondary acicular O phase precipitated during aging. The increase of secondary acicular O phase content reduces the mean free path of dislocation movement and increases the precipitation strengthening effect, which leads to the increase of strength of the alloy at room and high temperature, on the contrary, the plasticity decreases.

关 键 词：TI-22AL-25NB合金 锻态组织 固溶温度 拉伸性能 

分 类 号：TG166.5[金属学及工艺—热处理]