Numerical simulation of the temperature field in resistance seam welding for fabricating Fe-based amorphous coatings

A Fe-based amorphous coating was successfully fabricated on SUS304 using resistance seam welding (RSW), and the thermal cycling history during the welding process was measured. Based on the Comsol, the electric-thermal coupling finite element method (FEM) was adopted to analyze the dynamic distribution of current density and temperature field during the fabricating process, as well as the heat exchange mechanism. By comparing the experimental and simulated results of the temperature field, it can be concluded that the error in the temperature thermal cycle curve between the simulation and experiment at the same position is very small, which verifies the reliability of the electric-thermal coupling FEM in calculating the temperature field of the Fe-based amorphous coating fabricated by RSW. The simulation results indicate that the high current density area mainly exists at certain points at the bottom of the powder layer directly under the electrode wheel, and the adjacent areas centered on the left and right ends of the contact surface between the electrode wheel and the powder layer. The temperature field during the fabricating process of Fe-based amorphous coatings is not only related to the distribution of current density but also influenced by the movement of the electrode wheel and the heat exchange between the coating and the surrounding region. When the fabrication process is stable, the peak temperature remains almost unchanged in the longitudinal direction. In the x-z cross-section, there is a ‘concave’ distribution with higher temperature on the left side, lower temperature in the middle, and intermediate temperature on the right side. The corresponding thermal cycle curve shows an overall increasing trend of ‘rise-fall-rise’.