铝合金焊接接头冲击强化的性能
Performance of shock processing on aluminum alloy welded joint
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摘要: 为了提高铝合金焊接接头的力学性能,试验分别采用超声波和调Q脉冲YAG激光对A6061-T6铝合金焊接接头焊趾附近处进行冲击强化,研究了超声波和激光冲击强化下铝合金焊接接头的性能.两种冲击强化模式下,铝合金焊接接头焊趾处近表面均发生了冲击强化效果,并产生了较大的残余压应力,超声波和激光冲击强化后产生的最大残余压应力分别为 -158 MPa和 -145 MPa左右.超声波与激光冲击强化铝合金焊接接头的疲劳寿命差别不大,均比焊态下试样的疲劳寿命提高1倍以上.两种冲击强化方法的疲劳试验样件断裂位置均发生在基体金属上,而焊趾处没有疲劳裂纹产生.Abstract: In order to improve the mechanical properties of aluminum alloy welded joints, this paper respectively applied ultrasonic and Q-switch YAG laser shock processing on the weld toe of A6061-T6 aluminum alloy welded joints to study the performances of aluminum alloy welded joints after shock processing. Under two shock processing modes, the near surface on weld toe of aluminum alloy welded joints generated shock strengthening effect,and greater compressive residual stress was produced. The maximum compressive residual stresses generated by ultrasonic and laser shock processing were about -158 MPa and -145 MPa, respectively. The fatigue life of aluminum alloy welded joints after ultrasonic and laser shock processing was similar, increased more than one time compared to that of the welded specimen without shock processing. All specimens during fatigue test fractured in the base metal, and no fatigue crack occurred near the weld toe.