Effect of heat treatment and extrusion on wear properties of AZ91-Pr alloy

Abstract The effects of extrusion and T6 heat treatment on the microstructure of AZ91-Pr alloy and its wear properties under different applied loads were investigated. The extrusion refined the grains by dynamic recrystallization and grain breakage. The T6 heat treatment resulted in a more uniform distribution of β-Mg 17 Al 12 . Compared with the as-cast alloy, the hardness of the extruded alloy was increased by 18.8 %, and the T6 heat-treated alloy was increased by 58.4 %. The wear rate and friction coefficient of the three alloys increased with load. Under the same conditions, the values of the alloy after T6 treatment are the lowest and the values of the as-cast alloy are the highest. Abrasion and delamination were the wear mechanisms at the load of 30 N, and delamination and oxidation were the wear mechanisms at the load of 60 N. The wear mechanisms at 90 N load were plastic deformation and delamination.