Effect of homogenization treatment on the microstructure and mechanical property evolutions of As-cast Al-Cu alloy during high-pressure torsion

As-cast and homogenization treated as-cast Al-Cu (3 mass% Cu) alloy samples were processed via high-pressure torsion (HPT) under an applied pressure of 8GPa with 5 revolutions at room temperature. Microstructure, mechanical properties, and fracture surface morphology of the HPT-processed Al-Cu were investigated, demonstrating that the HPT process successfully resulted in distinct grain refinements in both samples. Significant improvements in the microhardness, tensile properties, and deformation homogeneity due to fine grains, high grain boundary misorientation angle, and homogeneous distribution of the θ phase were achieved after the HPT process of the homogenized sample. The homogenization treatment of the as-cast Al-Cu has a significant effect on the fracture surface morphology and fracture mode of the HPT-processed samples.