A Finite Element Model for Thermal Analysis of Stationary Co2 Continuous Wave Laser Beam Welding of AISI 304

An axisymmetrical finite element model is presented for numerical simulation of heat transfer in a continuous 2 CO laser beam welding of 304 stainless steel with two kinds of shielding gases. To approach the real case all thermo-physical properties were allowed to change with emperature and effects of phase changes- fusion and vaporization- were also taken into account in modeling. Thermal cycle, either during heating and cooling phase has been elaborated. Due to importance of cooling rate in steel’s microstructure and hence weld’s quality and strength, it has been calculated and its effects on metallurgical phases and granules’ size have been discussed. Weld dimension are predicted and compared with experimental results to ensure accuracy of the presented model. Effect of incident duration on weld dimensions, maximum temperature experienced by the specimen and the spatial temperature rate has been investigated. It has been shown that a saturation time occurs which is vital for a time and cost effective manufacturing welding process.