快运货车耐候钢薄板CMT焊接工艺及变形规律研究

Study on CMT welding technology and deformation law of weathering steel sheet for high speed heavy load truck

耐候钢薄板的应用是解决快运货车轻量化的核心技术。针对耐候钢薄板焊接过程中热输入量大、容易烧穿和产生较大变形的问题,选用CMT焊接方法实现了1.5 mm耐候钢薄板的焊接参数优化,采用最优参数模拟对比CMT焊接与传统耐候钢焊接方法(MAG焊)的变形量。结果表明:全熔透接头性能较好,增加焊接速度可以减少接头错边量,提高接头性能,接头抗拉强度最高达到669.6 MPa;模拟结果显示CMT焊接变形趋势与MAG焊接相似,焊缝中心与板边缘变形较大,CMT最大焊接变形量为+3.8 mm,MAG焊接最大变形量为+4.8 mm,CMT焊接变形明显小于MAG焊。

The application of weathering steel sheet is the core technology to solve the lightweight of high speed heavy load truck. In order to solve the problems of large heat input,burn through and large deformation during the welding process of weathering steel sheet,the CMT welding method is used to optimize the welding parameters of 1.5 mm weathering steel sheet,and the optimal parameters are used to simulate and compare the deformation of CMT welding with that of traditional welding（MAG welding）for weathering steel. The results show that the properties of the full penetration joints are good,and increasing welding speed can reduce joint misalignment and improve the joint property,the tensile strength of joint peaks at 669.6 MPa;the simulation results show that the deformation trend of CMT welding is similar to that of MAG welding,the deformation of weld center and edge plate are large,the maximum CMT welding deformation is ＋3.8 mm,the maximum MAG welding deformation is ＋4.8 mm,the CMT welding deformation is obviously smaller than MAG welding deformation.