Microstructure and mechanical properties of 2219 Al-alloy heat-affected zone with twin wire welding

Microstructure and mechanical properties changing rules of 2219 Al-alloy HAZ(heat-affected zone) with twin wire welding were studied using welding thermal simulation method.The result shows that the temperature interval of soften zone is 400-500℃ for 2219 Al-alloy twin wire welding,and 450℃ is the most serious temperature.The minimum strength is only 60% of the base metal with normal cooling rate.And property of HAZ is damaged more seriously with slower cooling rate,so increasing cooling rate can be used to strengthening HAZ.Effect of peak temperature on fracture type is small,and the alloy fractures are all ductile rupture.