Ti5321钛合金BASCA处理不同冷却速度下的片层形态和性能研究  

Lamellar Features and Mechanical Properties of Ti5321 Alloy at Different Cooling Rates of BASCA Treatment

作　　者：周伟[1] 赵永庆[1,2] 辛社伟[1] 李倩[1] 贾蔚菊[1] 王欢 张思远[1] 李思兰[1] 毛成亮[1] Zhou Wei;Zhao Yongqing;Xin Shewei;Li Qian;Jia Weiju;Wang Huan;Zhang Siyuan;Li Silan;Mao Chengliang(Northwest Institute for Non-ferrous Metal Research,Xi’an 710016,China;Northwestern Polytechnical University,Xi’an 710072,China)

机构地区：[1]西北有色金属研究院,陕西西安710016 [2]西北工业大学,陕西西安710072

出　　处：《稀有金属材料与工程》2020年第7期2314-2318,共5页Rare Metal Materials and Engineering

基　　金：National Natural Science Foundation of China(2015DFA51430)。

摘　　要：为了研究冷却速度对新型高强韧钛合金Ti5321显微组织和力学性能的影响,研究了Ti5321合金在不同β固溶缓冷时效处理(BASCA)处理后的组织和力学性能。结果表明,Ti5321合金β区固溶后缓慢冷却过程中冷却速率对α片层尺寸有决定性影响。片层尺寸随着冷却速率的减小而增大,片层在长度方向的生长速率远快于厚度方向。同时,随着冷却速度的降低,合金的强度降低。但损伤容限特性显示出强度的反向趋势。当冷却速度为0.5℃/min时,合金抗拉强度超过1200 MPa、同时具有良好的断裂韧性(KIC≥65 MPa·m^1/2)。The effects of three cooling rates on lamellar morphology and mechanical properties for Ti5321 alloy underβ-annealing with subsequent slow cooling and aging(BASCA)heat treatment were studied.The results show that the cooling rates play a decisive role in theαlamellar size formed with slow cooling process afterβzone solution.The lamellar size of Ti5321 alloy keeps increasing with the decrease of cooling rate,and the growth rate of lamellar in the length direction is much faster than that in the thickness direction.With the increase of cooling rate,the strength of the alloy will increase,but the fracture toughness will decrease.The cooling rate of 0.5 oC/min in this experiment is the optimal cooling way.The ultimate tensile strength of the alloy treated with this rate can exceed 1200 MPa with an excellent fracture toughness(KIC≥65 MPa·m^1/2).

关 键 词：钛合金 β热处理 力学性能 片层特征 

分 类 号：TG146.23[一般工业技术—材料科学与工程]