Effect of Cu and Ni interlayers on interfacial microstructure and shear properties of aluminum/steel dissimilar metal friction stir lap welded joints
The 6061-T6 aluminum alloy and QP1180 steel with Cu and Ni interlayers were welded by friction stir lap welding(FSLW)to study the microstructure of the joints and the mechanical properties were studied.The results show that Al-Cu-Fe and Al-Ni-Fe joints with good formability are successfully prepared by FSLW,and both Cu and Ni powders are well combined with the matrix.The Cu powder in-hibits the element diffusion between Al-Fe,the intermetallic compounds(IMCs)in the joints are AlCu and Al3Cu2,and no Al-Fe IMCs are generated.Ni powder can not entirely inhibit the reaction between Al-Fe,resulting in the presence of Al3Ni2 and AlFe3 IMCs in the joint.The average lattice mismatch of IMCs and matrix in Al-Ni-Fe joint is lower than that in Al-Cu-Fe joint,indicating that the bonding strength between IMCs and matrix in Al-Ni-Fe joint is better than that in Al-Cu-Fe joint.Therefore,the shear strength of Al-Ni-Fe joint(7.86 kN)is better than that of Al-Cu-Fe joint(4.62 kN).
friction stir lap weldingaluminum/steel interfaceintermetallic compoundslattice mismatchshear properties
万方数据
维普
