The dissimilar metals of 2.5 mm AZ31B magnesium alloy and 2 mm DP600 high strength steel were welded by friction stir lap welding.The effects of process parameters on the microstructure,binding mechanism and mechanical properties of magnesium/steel lap joints were investigated by OM,SEM,XRD,tensile test and hardness test.The results show that the connection mechanism of magnesium/steel joints was mechanical bonding.The tensile properties of the joints decreased when the welding feed rate in-creased;The tensile properties of the joints first increased and then decreased when the rotation speed in-creased.The maximum shear failure load of 295.8 N/mm was reached at the feed speed of 80 mm/min and the rotation speed of 900 r/min.The grain refinement at the interface was significant,and the hardness is significantly higher than that of the base metal.
关键词
镁合金/高强钢/搅拌摩擦搭接焊/接头性能
Key words
magnesium alloy/high strength steel/friction stir lap welding/joint performance
维普
万方数据