Weldability of dissimilar joints between aluminium wrought alloy A5052 and aluminium casting AC4C by high energy density welding processes

摘要

Weldability of dissimilar joints, mainly formed by the electron beam welding process, between Al-Mg group wrought alloy A5052 and Al-Si-Mg group alloy casting AC4C was investigated. In addition, the characteristics of dissimilar joints welded by high energy density welding processes such as laser welding and plasma arc welding were also examined. The results may be summarised as follows: 1 Dissimilar electron beam welded joints between aluminium wrought alloy A5052 and aluminium casting AC4C-T6 have improved tensile properties and impact properties compared with joints between A5052 and AC4C-F. 2 Using laser welding, deep penetration cannot be achieved and there is a marked occurrence of porosities. On the other hand, further investigation is required on the application of plasma arc welding. 3 Assessment of local mechanical properties was carried out for dissimilar welds between aluminium wrought alloy and aluminium casting alloy using circular notched tensile test specimens and impact test specimens with varied notch positions.