高频超声冲击处理对钛合金激光填丝焊组织和性能的影响研究  

Research on Effect of High-frequency Ultrasonic Impact Treatment on Microstructure and Properties of Titanium Alloy Laser Wire Filling Welded

作　　者：崔爱永 孙伟奇 赵佳磊 魏华凯 刘浩东 韩莉 CUI Aiyong;SUN Weiqi;ZHAO Jialei;WEI Huakai;LIU Haodong;HAN Li(Qingdao Campus,Naval Aviation University,Qingdao 266041,China;School of Mechanical Engineering,Liaoning University of Technology,Jinzhou 121001,China)

机构地区：[1]海军航空大学青岛校区,山东青岛266041 [2]辽宁工业大学机械工程与自动化学院,辽宁锦州121001

出　　处：《新技术新工艺》2025年第3期60-66,共7页New Technology & New Process

基　　金：山东省自然科学基金面上项目(ZR2022ME217)。

摘　　要：为提升TC4钛合金激光填丝焊接(laser wire filling-welded,LWFW)的疲劳性能,采用高频超声处理技术(high-frequency ultrasonic impact technology,HUIT)对焊接件实施焊后冲击处理,对冲击前后的显微硬度、断口形貌、疲劳性能微观组织、物相组成进行对比分析。结果表明:高频超声处理技术使得焊缝表层晶粒细化,但未影响其物相组成,仍以马氏体α′相为主。塑性滑移形变的硬化效应使焊缝表层显微硬度较冲击前提高约12%,较母材提高约40%;HUIT对TC4钛合金激光填丝焊接件的疲劳极限相比较未冲击提高了24.4%,高频超声处理技术后的钛合金激光填丝焊接接头的疲劳极限达到母材的86.6%,高频超声处理技术后裂纹在接头内部扩展,疲劳条带间距变小,瞬断区韧窝密集且加深,抗疲劳加载载荷越多,有效改善了TC4钛合金激光填丝接头的疲劳性能。In order to improve the fatigue properties of the TC4 titanium alloy laser wire filling-welded(LWFW),the high frequency ultrasonic impact technology(HUIT)was used to implement post-weld impact treatment on the welded part,and contrasted and analyzed microhardness,fracture morphology,fatigue properties microstructure,and phase composition before and after impact.The results showed that the HUIT made the weld surface grain fine,but did not affect its phase composition,which was still dominated by martensiticα′phase.Due to plastic slip-induced strain-hardening,the micro hardness of the weld surface layer increased about 12% higher than that before the HUIT and about 40% higher than that of the base metal.Compared with the before HUIT,the fatigue limit of TC4 titanium alloy LWFW joints was increased by 24.4%,and the fatigue limit of the titanium alloy LWFW joints after HUIT reached 86.6% of the substrate.After HUIT,cracks expanded in the interior joint,the fatigue band spacing became smaller,and dimples were denser and deeper,while the fatigue load increased,which effectively improved the fatigue property of the TC4 titanium alloy LWFW joints.

关 键 词：高频超声处理技术 激光填丝焊 显微硬度 疲劳寿命 断口形貌 

分 类 号：TG456.7[金属学及工艺—焊接] V267.44[航空宇航科学与技术—航空宇航制造工程] TG406[一般工业技术—材料科学与工程] TG146[金属学及工艺—金属材料]