Numerical Study of Temperature and Stress Fields in Laser Cutting of Aluminium alloy Sheet

摘要

Due to thermal nature of laser cutting, high temperature and thermal stresses are developed at the cut edge that affects finally the cut edge quality. This paper aims for developing a numerical simulation model to predict the temperature and residual stresses in the laser cutting of Aluminium alloy (Al-2024).The temperature and stress fields developed in cut section are predicted numerically using ANSYS finite element code. For the analysis, Fourier law of heat conduction and Gaussian distribution of a laser beam are considered. Temperature dependent thermo-physical properties of the material are used in numerical simulation. It is found that high temperature gradient exists at laser irradiated spot which results in high thermal stresses across the cut section. Also it has been found that the maximum temperature obtained during laser cutting is reduced with increasing laser scanning velocity. Stress distribution results shows that stresses attains low values at laser irradiated spot because of the reduction of thermal expansion coefficient with increasing temperature. The comparison of results based on numerical simulation with the mathematical model shows good agreements.