搅拌摩擦焊中材料流动行为数值模拟的研究进展

搅拌摩擦焊是一种革命性的焊接技术。相比于熔化焊，搅拌摩擦焊在铝合金、镁合金等材料的焊接方面具有明显的优势。而搅拌摩擦焊过程中材料在熔化温度以下经历剧烈的塑性流动，这与传统焊接过程有着明显不同，因此非常有必要对搅拌摩擦焊过程中的材料流动行为进行研究。由于试验方法本身在空间与时间上的局限性，数值模拟成为研究搅拌摩擦焊过程中的材料流动行为的重要方法。分析搅拌摩擦焊过程中的物理过程，从数值方法、热源模型、边界摩擦模型、材料本构模型这四个方面介绍搅拌摩擦焊中材料流动行为的数值模拟的最新研究进展及相关应用。对当前搅拌摩擦焊材料流动模拟中存在的不足进行分析，提出未来研究中应关注的研究方向。

Recent Advances in Numerical Simulation of Material Flow Behavior during Frictions Stir Welding

Friction stir welding(FSW) is a revolutionary welding technology for joining metallic materials such as aluminum alloys and magnesium alloys. The advantages of FSW over traditional fusion welding stem from the fact that material experiences severe plastic flow at temperatures below melting point. Therefore, it is critical to study and understand the material flow behaviors in order to optimize the FSW processing condition. Due to the spatial and temporal limitations of experimental studying, numerical simulation becomes an importance methodology in studying the material flow behavior. The basic physical processes involved in FSW process are analyzed. Thereafter, the numerical simulation on the material flow behavior is reviewed regarding the numerical method, heat source model, frictional boundary condition and constitutive model. Finally, the recent applications of the numerical models are discussed. In addition, the shortcomings in the current models and key points for the future researches are also pointed out.