Effect of filler metal on microstructure and mechanical properties of welded SiCp/Al composites by dual beam laser welding

In this study, the microstructure and mechanical properties of SiCp/6005Al composite welded joints with three different filler metals were studied by dual beam laser welding method. The tensile strength of SiCp/Al composite welded joints with Al-Si welding wire (ER4043 and ER4047) is higher than that with Al-Mg welding wire (ER5356). The main reason for the difference of tensile strength of weld joints is that the brittle phase Al4C3 is formed by the interfacial reaction between SiC particles and Al matrix at high temperature. More Si content in ER4047 can effectively inhibit the interface reaction and reduces the consumption degree of SiC particles in the welded metal, therefore a large number of SiC particles are retained to improve performance of weld seam compared with the other two welding wires.