打印方向对3D打印马氏体时效钢电阻点焊接头形成过程的影响

Effect of Printing Orientation on Formation of Resistance Spot Welded Joint of 3D Printed Maraging Steel

为了满足汽车零部件的个性化定制和快速开发需求,3D打印材料在汽车中的应用逐步增加,但目前3D打印材料的点焊性能在汽车服役过程中是否满足需求尚不清楚。采用实验手段开展3D打印马氏体时效钢和DP600双相钢电阻点焊接头的形成过程及力学性能研究。研究发现,由于3D打印材料的材料属性及表面粗糙度与传统钢板有差异,接头形状和形核过程与传统钢板明显不同。同时3D打印材料/DP600接头的拉剪强度高于传统双相钢接头,满足使用要求。不同打印方向对接头性能有影响,45°打印方向的马氏体时效钢粗糙度约为90°打印方向的3倍,导致电阻点焊接头熔核的形成时间滞后;综合形核过程和力学性能,90°打印方向的马氏体时效钢点焊性能更优。

The application of 3D-printed materials in automobiles has increased to meet the demands of customization and rapid development of parts. It is unclear whether the spot welding performance of 3D-printed materials meets the demand during service of automobiles. Experimental methods were used to study the formation and mechanical properties of resistance spot welds of 3D printed maraging steel to DP600 dual-phase steel. Due to material properties and surface roughness differences between 3D-printed materials and traditional steel plate, there are differences in nugget growth and nugget profile compared with those of the traditional steel spot welds. The lap-shear strength of 3D-printed maraging steel/DP600 joint is higher than that of dual-phase steel joint, which meets the strength requirement. The printing orientation has influence on the joint’s performance. The surface roughness of the maraging steel with printing orientation of 45° is about three times of that of the steel with 90° printing orientation, which delays the nugget formation in the spot welding joint. Considering joint’s formation and mechanical properties, the maraging steel with printing orientation of 90°has better resistance spot welding performance.