Metallurgical and mechanical characterization of Cu electrolytic coating on Aluminium alloys

Aluminium and its alloys are attractive for many applications in chemical, automotive and aerospace industries because of their excellent properties as height\u2013 to\u2013 weight ratio, high electrical and thermal conductivities and good formability. In this work, a surface hardening process based on Cu electrolytic coating and subsequent diffusion heat treatments was studied for 7075 and 2024 aluminium alloys. The effect of temperature and time on the microstructure and the depth of hardening was studied by SEM, EDS, XRD and HV tests. The increasing of hardness and depth of hardening have been correlated to formation of different intermetallic phases in the surface coatings