Effects of Precipitation of Al_3Zr Particles on Microstructures and Properties of the Al-3.55Cu-1.51 Li-0.11Zr Alloy

摘要

Under single-step and double-step homogenization conditions, the precipitation behavior of Alsub3/subZr dispersoids and its effects on the microstructures and tensile properties of an Al-3.5Cu-1.5Li-0.11Zr alloy were investigated in the current study. It was found that a double-stage homogenization (460 °C/16 h, 520 °C/24 h) enhanced the uniformity of the Alsub3/subZr dispersoids distribution compared with the single-stage homogenized samples. Alsub3/subZr particles which are coherent with the matrix would inhibit the movement of dislocation induced by stress and also the migration of sub-grain boundary and grain boundary induced by thermal activation. The finer particle size and distribution more diffuse of Alsub3/subZr particles reduced recrystallization during hot rolling and solution heat treatment, improving the tensile properties of the as-aged sample.