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搅拌摩擦焊接（Ｆｒｉｃｔｉｏｎ Ｓｔｉｒ Ｗｅｌｄｉｎｇ）是最近发展起来的一种新的固态连接技术。它主要用于铝合金，可以得到小变形、低成本和高质量的焊接接头。本文提出一个基于三维热弹塑性有限元分析的传热和力学计算模型。利用该模型可以了解搅拌摩擦焊接过程中的温度分布和循环，并预测焊后的残余应力和变形。对６０６１－Ｔ６铝合金搅拌摩擦焊接进行了实例分析。传热分析表明，铝合金搅拌摩擦焊接时的最高温度不超过材料熔点的８０％，因而属固态连接，同时为预测焊接接头的组织性能提供依据。力学计算结果表明，搅拌摩擦焊接的残余应力与变形要比传统的熔化焊接方法小得多。工件中最大的残余应力大约只有母材屈服极限的２５％－３０％。计算结果与试验数据相近，可作为进一步研究搅拌摩擦焊接过程和优化焊接参数的有效工具。
Friction Stir Welding is a new solid state connection technology developed recently. It is mainly used for aluminum alloy, can get small deformation, low cost and high quality welded joints. In this paper, a heat transfer and mechanical calculation model based on three-dimensional thermo-elasto-plastic finite element analysis is proposed. The model can be used to understand the temperature distribution and circulation during friction stir welding and predict the residual stress and deformation after welding. Case analysis of 6061-T6 aluminum alloy friction stir welding was carried out. Heat transfer analysis shows that the maximum temperature of the friction stir welding of aluminum alloy does not exceed 80% of the melting point of the material, so it belongs to the solid state connection and provides the basis for predicting the microstructure and properties of the welded joint. Mechanical calculation results show that the friction stir welding residual stress and deformation than the traditional fusion welding method is much smaller. The maximum residual stress in the workpiece is only about 25% -30% of the yield point of the base metal. The calculated results are similar to the experimental data and can be used as an effective tool to further study the friction stir welding process and optimize the welding parameters.