Multi Response Optimization of Friction Stir Welding Process Variables using TOPSIS approach

Being a solid state welding process, the friction stir welding (FSW) is extensively used these days, to join difficulty-to-weld materials such as aluminium alloys and its composites. This study emphasizes on friction stir welding of aluminium matrix composite (AMC) reinforced with silicon carbide particle. The FSW tool geometry and process variables play a vital role in governing the joint strength. Size of the grain and the hardness at the weld region influences the joint strength. Process variables such as tool revolving speed, tool traverse speed and the tool pin profile are optimized with multiple responses such as % elongation, tensile strength and hardness. In the present study a technique for order preference by similarity to ideal solution (TOPSIS) approach is used to solve multiple response optimization problems. The optimal solution reveals that the multiple response characteristics of the FS welded AMCs can be improved through the TOPSIS approach.