Microwave hybrid heating based optimized joining of SS304/SS316

Abstract

In this study, the microwave hybrid heating process has been exploited to produce optimized joints of SS304/SS316. Three input parameters: materials of the specimens to be joined (X), grain-size of filler powder (Y), and processing time (Z) have been investigated to see their effects on two major joint properties: micro-hardness (P) and micro-tensile strength (Q). Welded joints of specimens have gone through mechanical characterization via Vicker's micro-hardness tests and also the micro-tensile strength examinations. Outcomes have been used further for finding optimal settings of input parameters to achieve the best mechanical properties of joints. Grain-size of filler material is the most significant parameter; followed by specimen material. On the other hand, process time has little influence on output parameters within the small incremental time range of only 60 s considered during this work. SS304-SS304 (X1) specimen materials with 70 nm (Y1) filler powder at 360 s (Z1) processing time input settings help in achieving optimal micro-hardness (Poptimal) and micro-tensile strength (Qoptimal). Microstructure test results of the developed joints reveal the formation of dense metallic microstructures across the joining region which justifies the reason for higher micro-hardness and micro-tensile strength of the joint region.