08Al钢TIG填丝焊与CO_2激光焊接头力学性能研究

Study on Mechanical Properties of 08Al Joint of TIG Welding with Wire and CO_2 Laser Welding

试验采用TIG填丝焊和CO2激光焊分别对2mm厚08Al钢进行对接焊,通过静拉伸、弯曲试验及显微硬度测试研究了两种焊接接头的力学性能。结果表明,CO2激光焊和TIG填丝焊拉伸试样均在母材位置发生断裂,拉伸强度均达到300 MPa;CO2激光焊接接头弯曲角度大于TIG填丝焊,弯曲达到180°后未出现微观裂纹;08Al钢TIG填丝焊和CO2激光焊接接头显微硬度从熔化区到母材整体呈现下降趋势,而TIG填丝焊在靠近母材附近的热影响区出现显微硬度的小幅度上升,CO2激光焊在部分相变区出现小幅度的上升;CO2激光焊接接头熔化区显微硬度波动大于TIG填丝焊。

The 2 mm thick 08A1 plate was welded through TIG welding with wire and CO2 laser welding respectively. The experiment studied the mechanical properties of two kinds of welded joint by tensile strength, bending performance and microhardness test. Tensile samples of CO2 laser welding and TIG welding with wire snapped both in the base metal and the tensile strength both arrived to 300 MPa. The bending angle of CO2 laser welding joint was bigger than TIG welding with wire and it was able to reach 180° without microscopic crack. The microhardness of the two kinds of joints declined from fusion zone to base material and the both had a small rise severally in the heat affect zone and the non-full transformation zone,and the experiment found that the fluctuating value of CO2 laser welding was more than TIG welding with wire in fusion zone.