A study on induction welding of mild steel and copper with flux under applied load condition

In the present study, Induction welding was carried out to achieve the joining between dissimilar metals such as mild steel (AISI 1015) and copper (Cu) in open atmosphere with different loads and different current settings. Microstructural evaluation of the welded joints was done by optical microscope and scanning electron microscope (SEM). The study showed that Cu was well bonded with mild steel (MS) without any crack near diffusion line. The X-Ray Diffraction (XRD) analysis was carried out and it revealed the presence of FeCu4 and Cu(Fe2O4) along with Cu and Fe. Joint quality was examined by measuring ultimate tensile strength (UTS) and microhardness. The UTS of the welded specimens was found to be increasing with the increase of load and current. The maximum UTS was obtained for specimen welded at 650 A with 2.5 kg load applied during welding. Microhardness distribution of the welded specimens showed that microhardness at interface line was more than that of copper and less than that of mild steel. The maximum microhardness on the copper side was at the interface line and attained base metal microhardness 1 mm onward from the interface. However the microhardness on mild steel side increased nearly upto 6 mm from the interface line.