焊趾TIG熔修对7075铝合金接头残余应力的影响

摘要

In order to research the influence of welded toe TIG dressing process on 7075 aluminum alloy T-joint, we use ABAQUS finite element method to establish physical model and analyse the residual stress distribution of welded toe. The residual stresses of welded toe were also measured by using the blind-hole method. The results indicate that after TTG dressing, the longitudinal residual stresses in welded toe of steel joint are gradually transited from tensile residual stresses to compressive ones, and there is no significant change for transverse residual stresses. The TIG dressing treatment can not only improve the residual stress distribution, but also make the surface of welded toe transferred smoothly, which is useful for the increase of fatigue strength.%为了研究焊趾TIG重熔处理工艺对7075铝合金T型接头残余应力状态的影响,采用ABAQUS有限元法建立有限元物理模型分析了焊趾部位残余应力分布状态,并采用盲孔实验法测定了焊趾部位的残余应力值.结果表明,经TIG重熔处理后,焊趾部位的残余应力值有所降低,纵向残余应力由焊态的拉伸应力状态过渡到重熔后的压缩应力状态；横向残余应力为压缩应力状态,应力值略有降低.焊趾TIG重熔工艺不仅改善了焊趾部位的残余应力状态,同时使焊趾部位表面圆滑过渡,从而有利于疲劳强度的提高.