Influence of processing parameters on joint characterization of SS 304 using microwave hybrid heating

Abstract

In this study, the microwave hybrid heating process has been explored to produce optimized joints of stainless steel 304. During the experiment, IFB microwave with a 900W output power and a fixed frequency of 2.45 GHz was employed. Three process parameters: microwave welding time, powder size, and slurry weight have been investigated to see their effects on three major joint properties: tensile strength, micro-hardness and surface temperature. In order to identify the optimum settings for the process parameters to provide the best mechanical qualities for joints, Taguchi L9 was used as the design of the experiment. Microwave welding time is the most significant parameter; followed by powder particle size and slurry weight has little influence on output parameters. More welding time & slurry weight with lower powder particle size produced the best results out of the values chosen as processing parameters. The tensile strength was determined to be 499 MPa. The microhardness of the joint region resulting in a value of 452 Hv. X-ray diffraction images of joint area show the presence of nickel and carbides phases. Microstructure and SEM pictures revealed that the substrate and slurry were properly mixed. The maximum temperature on the surface of the joint was found to be 926.3°C. FESEM images of broken joint showed mixed mode of failure (ductile and brittle).