异种金属搅拌摩擦焊AA5083和AA6082合金的搅拌区和热力影响区的变化

摘要

研究AA5083-O和AA6082-T6合金异种金属搅拌摩擦焊接头的成分、显微硬度(热力影响区)和织构的变化.采用电感耦合等离子体?原子发射光谱法测定焊缝区主要合金元素的含量.结果表明,搅拌摩擦焊过程中两种合金的主要合金元素的含量均略有下降,其中镁元素含量的变化最大.通过将两种合金母材与搅拌区的主要合金元素的质量分数相联系,估算搅拌区两种合金的相对比例,结果显示,焊缝后退侧的材料占比大于60％.另外,后退侧热力影响区硬度分布的变化主要受该区域晶粒尺寸变化的影响.最后,研究进一步表明,轴肩区与搅拌针区的织构成分不同.%Variations in composition, microhardness (in the thermomechanically affected zone) and texture in the tool domain of the dissimilar friction stir weld of AA5083-O and AA6082-T6 alloys were investigated. The contents of the major alloying elements in the weld zones were determined using inductively coupled plasma?atomic emission spectroscopy. It was observed that a slight drop in the content of the alloying elements results from the friction stir welding process with the Mg content being the most affected amongst the major alloying elements in the two alloys. By relating the mass fractions of the major alloying elements in the parent metals of both alloys to those of the stir zone, the relative proportions of the two alloys in the stir zone were estimated with the results showing that at least 60％ of the materials in the stir zone are from the retreating side of the weld. It was also revealed that the changes in the hardness profile in the thermomechanically affected zone of the retreating side are predominantly influenced by changes in grain size in that domain. Finally, the investigation further revealed that the texture component in the tool shoulder domain is different from the texture component in the tool pin domain.