摘要
This investigation is aimed to establish empirical relationships between continuous multi-seam friction stir cladding process parameters （i.e., rotational speed, welding speed and shoulder overlap ratio） and the quality characteristics （bond tensile strength, shear strength and corrosion） of dissimilar magnesiurn-aluminium alloy clad joints. The influence of considered process parameters on the clad properties was reported. Furthermore, multi-criterion optimization procedure was used to obtain ideal processing conditions, which can yield higher interface strength and lower corrosion rate of fabricated composite plate. Results indicate that, the aluminium-rich thin continuous layer, Mg-rich irregular shaped regions consists of A13Mg2 and Al12Mg17 interraetallic compounds and nature of mechanical interlocking has great influence on the joint interface strength. On the other hand, the corrosion resistance of the clad joints is greatly affected by the amount of magnesium mixed with top aluminium sheet during friction stirring. Also, bend testing shows that, the cladded joints exhibit excellent ductility.
建立了异种镁铝合金包覆接头连续多缝搅拌摩擦包覆工艺参数(旋转速度、焊接速度和重叠比)和质量表征(结合抗拉强度,剪切强度和腐蚀)的经验关系,研究了工艺参数对包覆性能的影响。采用多尺度优化过程得到了理想的加工条件,在该条件下制备得到的复合板具有较高的界面强度和较低的腐蚀速率。结果表明,薄的富铝连续层和不规则富镁区由金属间化合物Al_3Mg_2和Al_(12)Mg_(17)组成,机械联锁的性质对接头界面强度有很大的影响。另一方面,在搅拌摩擦过程中镁混合到铝板的量对包覆接头的耐蚀性影响很大。弯曲测试表明,包覆接头具有优良的延展性。
