Achieving a Better Combination of Strength and Electrical Conductivity of Cu-Al2O3 Nanocomposites by Accumulative Roll-Bonding to Ultrahigh Cycles

Copper matrix nanocomposites reinforced by Al2O3 nanoparticles were fabricated by accumulative roll-bonding (ARB) processed to ultrahigh rolling cycles. The effects of ARB cycles on the distribution of Al2O3 nanoparticles and properties of the nanocomposites were investigated. It was found that a higher ARB cycle was needed to obtain a uniform distribution of Al2O3 nanoparticles with a larger volume fraction. Significant strengthening, as well as a good combination of tensile strength and electrical conductivity of the Cu-Al2O3 nanocomposites can be obtained, through optimizing the uniform dispersion of Al2O3 nanoparticles by applying ultrahigh ARB cycles. The enhanced strength (maximum: 735 MPa) of the nanocomposites can be attributed to the maximized contribution of nanoparticles by various mechanisms through optimizing the uniform dispersion of them.