基于显微硬度图的AA6061合金搅拌摩擦焊接接头的力学和冶金性能表征

摘要

研究搅拌摩擦焊接接头 AA6061-T913的显微硬度与其显微组织、宏观组织和力学性能的关系。根据整个焊件的硬度，提出3个方程式分别预测焊件合金的晶粒尺寸、极限拉伸强度和屈服强度。根据所建立的方程式，绘制关于晶粒尺寸的二维图以及关于极限拉伸强度和屈服强度的三维图。根据硬度分布曲线，确立宏观区域的位置，并将模型所得结果与显微观察及拉伸试验结果进行比较。结果表明：模拟结果与实验结果吻合较好。对于极限拉伸强度和屈服强度，其模拟结果与实验结果的平均误差分别为8%和3%。%The relationships between microhardness and microstructure, macrostructure and mechanical properties of friction stir welded joints AA6061-T913 were studied. Three equations were suggested to predict the grain size, ultimate tensile strength and yield strength from the hardness throughout the weld. Two-dimensional contour of grain size and three-dimensional maps of ultimate tensile and yield strengths were plotted according to the proposed equations. Also, the location of macroscopic zones was estimated based on hardness distribution. The modeling results were compared with the results obtained from microscopy and tensile tests. The modeling results show good agreement with the experimental findings, and the average differences between them for the ultimate tensile strength and yield strength were about 8%and 3%, respectively.