Models of plasma arc welding

Abstract

A complex model of energy transfer from ionized gas through a weld-pool to a heat a®ected zone (HAZ) is considered here. The model consists of three sub-models: a model of the arc column with skin layers - sheaths coating elec- trodes, a model of liquid metal °ow in a weld-pool, and a model of coupled thermo-mechanical-metallurgical processes in HAZ. These sub-models are de- scried in three reports. The ¯rst report is devoted to a short review of welding plasma models based mostly on the Magneto-Hydro-Dynamics (MHD) the- ory successfully applied to the simulation of welding process. This report is illustrated by arc models for TIG and PAW welding. The description of ther- mal energy transfer between three sub-regions of the complex welding domain refers to a large number of processes observed in gaseous electronics, ther- modynamics of reacting gases, electro-dynamics of °uid, micro-metallurgy.