差厚铝合金2024∕7075搅拌摩擦焊的温度场数值模拟

Numerical Simulation of Temperature Field in Friction Stir Welding of Aluminum Alloy 2024/7075 with Different Thicknesses

利用Abaqus有限元软件,建立差厚7075和2024铝合金的有限元模型和改进热源模型,进行模拟搅拌摩擦焊的焊接过程,分析了不同厚度比的温度分布,以及对焊核区和热力影响区的宽度变化的影响,并验证了所建模型应用的可行性。结果表明,铝合金焊件中的温度峰值随着厚度比的变化而改变,且温度在铝合金板上呈不对称的倒“V”形分布,板材上的温度峰值随着板材厚度变大而减小。焊接过程中温度越高焊件上的热力影响区就越宽。较大的厚度比会使得焊件的热力影响区宽度和焊核区宽度偏大。模拟得到的温度值和试验数据比较,两者的误差在8%以内,验证了模型的可行性。

Using Abaqus finite element software,the finite element models and improved heat source models of 7075 and 2024 aluminum alloys with different thicknesses were established to simulate the welding process of friction stir welding.The temperature distribution of different thickness ratios and their effects on the width changes of the weld nugget zone and thermal affected zone were analyzed,and the feasibility of the application of the built model were verified.The results indicate that the temperature peak in aluminum alloy weldments varies with the thickness ratio,and the temperature distribution on the aluminum alloy plate is distributed asymmetrically in an inverted“V”shape.The temperature peak on the plate decreases with the increase of plate thickness.The higher the temperature during welding,the wider the heat affected zone on the weldment.A larger thickness ratio will cause the width of the heat affected zone and the width of the weld nugget zone of the weldment to become larger.The comparison between the simulated temperature values and experimental data shows that the error between the two is within 8%,which verifies the feasibility of the model.