Modeling of heat transfer and fluid flow in the metal being welded during DC and HFPC TIG spot welding

A mathematical model of non-stationary electromagnetic, heat and mass transfer processes in the metal during high frequency pulsed current (HFPC) TIG spot welding has been proposed. A computational algorithm for the the numerical solution of the corresponding mathematical problems has been developed and implemented in Wolfram Language. A comparative analysis of the hydrodynamic and heat transfer processes in the specimen of steel S-235JR during HFPC TIG welding with 10 kHz square wave pulse current modulation and direct current (DC) TIG welding with current equal to the mean current of HFPC mode has been carried out. As simulations showed, the HFPC modulation results to appreciable weld penetration with minor influence on the radius of the fusion zone compared to the DC process.