Study on A-TIG repair welding for the cast magnesium alloy

The effect of the weld technology of TIG and A-TIG on the penetration and welding defects was carried out by the simulation experiments of repairing hole defects. Based on the results of hole healing with different size, it was shown that at the same welding parameters the depth of healing holes in A-TIG process was obviously higher than that of TIG,and the welding induced porosity defect was less. Under the condition with the same depth of welding,the required TIG welding current was much larger than that of A-TIG, meanwhile the heat-affected zone (HAZ) microstructures was deteriorated and the welding defects was generated. The analysis revealed that A-TIG repair welding processing is better than that of TIG because of the interaction between activating fluxes and arcas well as the molten pool.