Effect of process parameters on tensile strength in plasma-MIG hybrid welding for 2219 aluminum alloy

2219 aluminum alloy is one of the most extensively used materials for the fabrication of rocket fuel storage box. This paper aims at revealing effect of process parameters on tensile strength in 2219 aluminum alloy welded by means of the plasma-MIG hybrid welding method. Process parameters such as MIG voltage, plasma gas, plasma current, welding speed, wire feed speed, etc. play a major role in deciding the joint tensile strength. An attempt has been made to establish an empirical relationship between process parameters and the tensile strength by applying a second-order regression model. A central composite design was applied to perform experiments for obtaining input-output data. The established model was tested for its adequacy and significance. Influences of single factor and interactive effect on tensile strength were analyzed. The maximum tensile strength of 2219 aluminum alloy jointed by plasma-MIG hybrid welding was 289.6 MPa.