变形量对Ti-22Al-25Nb合金环形锻件组织与拉伸性能的影响  

Effects of Deformation Amount on Microstructure and Mechanical Properties of Ti-22Al-25Nb Alloy Ring Forgings

作　　者：张晓越 师俊东 马雄 梁晓波 张建伟 曾卫东[3] ZHANG Xiaoyue;SHI Jundong;MA Xiong;LIANG Xiaobo;ZHANG Jianwei;ZENG Weidong(AECC Shenyang Engine Research Institute,Shenyang 110015,China;Gaona Aero Material Co.,Ltd.,Beijing 100081,China;School of Materials Science and Engineering,Northwestern Polytechnical University,Xi'an 710072,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]西北工业大学材料学院,陕西西安710072

出　　处：《热加工工艺》2023年第11期103-108,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合金环形锻件为研究对象,观察了不同变形量的环形锻件微观组织,研究了变形量对锻件室温拉伸性能、室温缺口敏感性和高温拉伸性能的影响,分析了断口特征。结果表明:随着变形量的增加,压扁B2晶粒的长短轴之比显著增加,一次初生板条O相含量明显增加,晶界析出相更加断续。变形量的增加同时提高合金的强度和伸长率。当变形量为50%时,环件试样达到了最佳的强度和塑性匹配。因B2晶粒尺寸减小的晶界强化作用和晶界析出相的不连续是合金的强度和塑性升高的主要原因。室温拉伸断口特征以解理刻面为主。随变形量增加,室温拉伸断口上二次裂纹增加,塑性断裂特征增加。Taking Ti-22Al-25Nb alloy ring forgings as the object,the microstructure of the ring forgings with different deformation amounts was observed,the effects of deformation amount on the room temperature tensile property,room temperature notch sensitivity and high temperature tensile property were studied,and the fracture characteristics were analyzed.The results show that with the increase of deformation,the ratio of long axis to short axis of flattened B2 grains increases significantly,the content of primary lath O phase increases significantly,and the precipitated phases at grain boundaries become more discontinuous.The strength and elongation of the alloy increase with the increase of deformation amount.The ring specimen with 50%deformation amount achieves the best combination of strength and ductility.The grain boundary strengthening effect due to B2 grain size decrease and the discontinuity of precipitated phases at grain boundary are the main reasons for the increase of strength and ductility of the alloy.The tensile fracture at room temperature is mainly cleavage facet.With the increase of deformation,the secondary cracks on the tensile fracture at room temperature increase,and the ductile fracture characteristics increase.

关 键 词：TI-22AL-25NB合金 环形锻件 变形量 拉伸性能 

分 类 号：TG335[金属学及工艺—金属压力加工] TG337.6