Joint performance of duplex stainless steel 2205 by laser-MIG hybrid welding

Phase ratio in weld metal and heat affected zone of duplex stainless steel will be unbalanced and joint properties deteriorated because of fast cooling rate after welding by conventional high energy density beam,so the duplex stainless steel 2205 is welded by using laser-MIG hybrid welding method,and the microstructure,mechanical property and corrosive property of welded joint are analyzed.The results show that the phase ratio of ferrite in weld metal and heat-affected zone is controlled between 40%-70%,the microhardness and tensile strength of the joint are higher than those of base metal,the impact toughness of weld metal,fusion line and heat-affected zone at-40 ℃ is 73,205,190 J/cm2 respectively,and the critical pitting temperature(CPT) of weld bead is 49 ℃,near the same as that of base metal.So the good joint performance of duplex stainless steel 2205 can be obtained by laser-MIG hybrid welding.