Effect of Nano-Sized TiC-TiB2 on Microstructure and Properties of Twin-Roll Cast Al-Cu-Mn-Zr Alloy

Al-5Cu-0.8Mn-0.1Zr strips produced during a twin-roll-casting process are investigated in this paper. Central segregation does occur in the alloy strip, and the segregation is a mixture of Al2Cu and Al20Cu2Mn3 eutectic phases. This mixture is difficult to be dissolved in solid solution heat treatment. In this paper, nano-sized TiC/TiB2 particles are introduced in the process of twin-roll-casting. It was found that after adding 0.3% nano-sized TiC-TiB2 particles, the composition distribution becomes more uniform, and the central segregation is eliminated, compared to the strip without nanoparticles. The tensile strength of T6-treated alloy increases from 350 MPa to 390 MPa when nanoparticles are added, and the goal of increasing the properties of twin-roll-cast Al-Cu-Mn-Zr alloy has been achieved.