| The method of stud welding of aluminum alloy has been studied in this dissertation. It was proved initially that inert gas protection is needed in the process of aluminum stud welding. Further compounded heat sources (CHS) technique, soak plating (SP) treatment on Al stud surface-CHS union technique, soldering powder assist (SPA) welding technique are used to modify the conventional aluminum alloy stud welding method. The mechanical properties, macro/micro configuration of the welding joint are studied to estimate the method and the effect of the technical parameters.A lot of falty fusion,gas hole and oxigenation appeared in the joint with ceramic ring only. The intension of the joint was enhanced by 34% when inert gas protection was used. When the welding current got too large, it would undermine the protective effect of the inert gas.The oxigenation on the surface of the Al board was wiped off by the TIG arc of the CHS effectively.The welding current decreased as the Al board was preheated; also, welding defects were more likely to appear as the welding current got larger and the protection effect was reduced by the splash.The oxidation of the Al board would cease after SP treatment, neither would the soak plate coating bring dedect into the welding joint. The intension of the joint was enhanced by 3.4 times. When welding current rose to a certain level, the affection of welding current to the quality of the joint was weaken. Fine weld organizations and high intension of the welding line would be gained under appropriate welding current.The oxidation coating would be cracked by the SPA and new oxygenation would not be made when welding. The intension of the joint was enhanced by 45.3% more than the joint without SPA. The intension of the welding reached 123 MPa. The strength of the joint increased with more soldering powder, but the protect affection was weaken by the gas produced in the decompound process, and the joint strength decreased remarkably.
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