Microwave Welding of Mild Steel

Abstract

In this research, microwave welding of mild steel has been carried out at different exposure time, and mechanical characteristics at the weld zone are examined. Commercial mild steel specimens with the dimension of 20 × 20 × 2 mm are used in this study. The process parameters used in the microwave welding are microwave frequency, interfacing material, power rating, susceptor, separator, exposure time. Microstructure, porosity, and hardness tests were performed to evaluate mechanical characteristics of the welded piece. Results show that the reliable welding was occurred between 630 and 840 s, below which the weld is partial and above which the specimen gets deformed. The microstructure of the weld region exposed clear grains of the austenitic structure. No porosity defect was perceived in the weld zone. The hardness at weld joint and on HAZ are 58–59 HRB and 51–52 HRB, respectively, and is more significant compared to the hardness of the base metal which is 49–50 HRB.