摘要
【目的】旨在研究超声振动复合TIG对HG70低合金高强钢焊缝成形特点、微观组织及力学性能的影响。【方法】以HG70低合金高强钢为试验材料,在钨极氩弧焊过程中辅助以超声振动,从而形成受激振动的焊接电弧。通过对焊接接头的微观组织的观察、硬度测量,分析有、无超声振动辅助对接头金相组织及力学特性的影响规律,并基于小孔法测试了有、无超声振动辅助下焊接接头的残余应力演化趋势。【结果】试验结果表明,钨极氩弧焊焊缝硬度峰值为238.2HV,经超声复合后硬度峰值为259.1HV,增加约9%;钨极氩弧焊焊缝纵向残余应力峰值为425MPa,经超声复合后焊缝纵向残余应力峰值为338MPa,降低约20%。【结果】通过焊接电弧的周期性超声振动形成对焊接熔池结晶过程的控制,细化晶粒,改善焊接接头组织,使焊缝的残余应力降低。
[Objective]The purpose is to investigate effects of ultrasonic vibration assisted TIG on formation characteristics,microstructure,and mechanical properties of HG70 high strength low alloy steel weld.[Methods]Taking HG70 high strength low alloy steel as test material,ultrasonic vibration is assisted during tungsten inert gas(TIG)welding process to form a stimulated vibrating welding arc.By observing microstructure and measuring hardness of welded joints,influence of ultrasonic vibration assistance on metallographic structure and mechanical properties of welded joints is analyzed.Based on drilling hole method,evolution trend of residual stress in welded joints with and without ultrasonic vibration assistance is also tested.[Results]The experimental results show that peak hardness of TIG weld is 238.2 HV,which increases to 259.1 HV after ultrasonic vibration assistance,an increase of about 9%.Peak longitudinal residual stress of TIG weld is 425 MPa,which is reduced to 338 MPa after ultrasonic vibration assistance,a decrease of about 20%.[Conclusion]By assisting periodic ultrasonic vibration to welding arc to control crystallization process of welding pool,grains are refined,microstructure of welded joints is improved,and residual stress in the weld is reduced.
作者
袁少波
彭国平
张勇
YUAN Shaobo;PENG Guoping;ZHANG Yong(Guangzhou Special Equipment Inspection&Research Institute,Guangzhou 510663,China;College of Materials Science and Engineering,Liaoning Technical University,Fuxin 123000,Liaoning,China)
出处
《焊接》
2025年第3期86-90,96,共6页
Welding & Joining
基金
广州市市场监督管理局科技项目(2020kj14)。
关键词
低合金高强钢
超声振动复合TIG
晶粒细化
残余应力
high strength low alloy steel
ultrasonic vibration assisted TIG
grain refining
residual stress
作者简介
第一作者:袁少波,硕士,高级工程师,主要从事特种承压设备无损检测研究,neverbo@126.com。
