退火处理对电子束焊接TC17钛合金组织与力学性能的影响  

Effect of annealing treatment on microstructure and mechanical properties of electron beam welding TC17 titanium alloy

作　　者：卞宏友 刘明松 刘伟军 刘晏硕 于兴福 Bian Hongyou;Liu Mingsong;Liu Weijun;Liu Yanshuo;Yu Xingfu(School of Mechanical Engineering,Shenyang University of Technology,Shenyang Liaoning 110870,China;Liaoning Provincial Key Laboratory of Laser Surface Engineering Technology,Shenyang Liaoning 110870,China)

机构地区：[1]沈阳工业大学机械工程学院,辽宁沈阳110870 [2]辽宁省激光表面工程技术重点实验室,辽宁沈阳110870

出　　处：《金属热处理》2025年第2期194-199,共6页Heat Treatment of Metals

基　　金：国家重点研发计划(2022YFB4602402)。

摘　　要：通过金相显微镜、扫描电镜、硬度计和拉伸试验机等研究了退火对TC17钛合金焊接接头显微组织和力学性能的影响。研究表明,在电子束焊接TC17钛合金焊缝处发生动态再结晶,生成了亚稳态β晶粒,晶粒无明显的第二相存在,导致焊缝区发生软化;随着距离焊缝越近,热影响区中的初生α相长宽比减小,次生α相逐渐溶解,导致显微硬度逐渐降低。600℃退火4 h后,焊缝硬度相较于焊态提高41%,热影响区硬度相较于焊态提高12.8%,由于焊缝、热影响区中的亚稳态β相内析出了细小弥散的次生α相,因此焊缝、热影响区的显微硬度与焊态相比明显提高。焊接接头处的性能主要由α相的大小和数量决定,退火后α相的强化效果明显,抗拉强度相比于焊态接头提高了14%,且接头抗拉强度高于基体,因此接头的断裂位置在基材。Effect of annealing on the microstructure and mechanical properties of TC17 titanium alloy welded joint was studied by means of metallographic microscope,scanning electron microscope,hardness tester,and tensile testing machine.The results show that dynamic recrystallization occurs in the weld seam of the TC17 titanium alloy,and metastableβgrains are formed,and there is no obvious second phase in the grains,which leads to softening of the weld zone.As the distance from the weld seam gets closer,the aspect ratio of the primaryαphase in the heat affected zone decreases and the secondaryαphase dissolves gradually,resulting in a gradual decrease in microhardness.After annealing at 600℃for 4 h,the hardness of weld seam is increased by 41%compared with that of the welded state,and the hardness of heat affected zone is increased by 12.8%compared with that of the welded state.Due to the fine and dispersed secondaryαphase precipitated in the metastableβphase in both the weld and heat affected zone,the microhardness of weld and heat affected zone is increased significantly compared with the welded state.The properties of the welded joint are mainly determined by the size and quantity ofαphase.After annealing,theαphase has obvious strengthening effect,the tensile strength of the welded joint is increased by 14%compared with that of the welded state,and the tensile strength of joint is higher than that of the substrate,thus the fracture position of the joint is on the substrate.

关 键 词：TC17钛合金 电子束焊接 热处理 显微组织 力学性能 

分 类 号：TG113[金属学及工艺—物理冶金]