焊接参数对搅拌摩擦焊搅拌区材料融合的影响

EFFECT OF WELDING PARAMETERS ON MIXING OF MATERIALS IN NUGGET ZONE OF FRICTION STIR WELDS

用率相关本构模型模拟了搅拌摩擦焊接过程,研究了焊接参数的变化对搅拌摩擦焊接构件横截面上材料变形的影响．通过对不同过程参数下等效塑性应变的研究,分析了搅拌区及热力影响区内焊缝中心线两侧材料的融合情况,根据变形分布,从理论上判断焊接参数的变化对焊接质量产生的影响．结果表明,在靠近焊接构件下部材料的融合随着搅拌头转速的增加和焊速的减小趋于良好,但是搅拌头转速过高有可能导致焊接缺陷的产生．

Rate dependent constitutive model is used to simulate the friction stir welding process. The effect of the process parameters on the material deformation on the transverse section of the friction stir weld is investigated. The materials mixing on the both sides of the welding line in the nugget zone and thermo-mechanical zone is studied by means of the research on the equivalent plastic strain distributions under different process parameters. The effect of the process parameters on the weld quality is herein judged from the material deformations. Results indicate that the materials mixing can be improved when the angular velocity of the pin is increased or the welding speed is decreased, but some flaws may occur when the angular velocity is too high.