Effect of post-heat treatment on friction surfaced Al-Cu-Mg alloy coating containing Ag

摘要

This study addresses the microstructural evolutions and mechanical properties of AA2024-16wt%Ag composite coatings prepared via friction surfacing process on an AA2024 aluminum alloy. The formation of Al-6(Cu, Ag)Mg-4 precipitates is confirmed by the X-ray diffraction analysis, attributed to the generated heat and plastic deformation induced by the friction surfacing process. It is shown that the solution heat treatments could promote solid solution formation, intensifying the precipitation of secondary phases in Ag-containing coatings. Furthermore, a higher density of the precipitates increases the hardness and strength of the Ag-containing coatings. However, increasing the heat treatment time adversely affects the strength and hardness of the coatings since it could promote excessive precipitation of the CuAl2, Al2CuMg, and Al-6(Cu, Ag)Mg-4 phases, as well as coarsening of the precipitates.