| 2008 №04 (01) | 2008 №04 (03) |
The Paton Welding Journal, 2008, #4, 5-10 pages
Numerical simulation of metal structure in haz in welding of increased strength steel
V. Pekarska
Politechnika Czestochowska, Poland.Abstract
A mathematical model is proposed, which describes the temperature field and phase transformations in laser welding. The temperature field is determined by the equation of an unsteady heat flow with a convection term using Green’s function. Model of the phase transformations in solid state for the steel being welded is based on assumption of continuous cooling and Avrami, Koistinen and Marburger equations. Volume fractions of phases during cooling are defined as functions of the cooling temperature and rate, and deformation increment depends upon the temperature and phase transformations. Metal structure in the welded joint HAZ was evaluated.
Keywords: laser welding, temperature field, heat-affected zone, thermal cycle, dilatograms, phase transformations, structure, mathematical model
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