Temperature field and flow field during tungsten inert gas bead welding of copper alloy onto steel

The temperature field in the base metal and bead-on-plate weld during tungsten inert gas bead welding Hs201 copper alloy onto 35CrMnSiA steel was studied and the fluid flow of the partially melted steel in the molten pool was analyzed. The results show that the thermal cycle changes remarkably and the peak temperature and the cooling speed in the fusion interface are higher than those far away from the interface. In the liquid overlay, the velocity of the fluid flow of the partially melted steel in the edge of the overlay points to the fourth quadrant, while in the puddle of the base metal, the velocity vector points to the second quadrant. Based on the calculated flow field, the distribution of the Fe-rich phase is predicted. The melted steel is driven to the boundary of the overlay. The distribution of Fe-rich phase is largely more in the outside periphery of the overlay than in the middle of the overlay.