Tensile behavior and strengthening mechanism in ultrafine TiC0.5 particle reinforced Cu-Al matrix composites

Strength and ductility are two of the most important, but often mutually exclusive, mechanical properties of structural materials. Here we report a new kind of nonstoichiometric TiC0.5 reinforced Cu-Al matrix composite fabricated by sintering a coarse particle mixture of Ti2AlC and Cu. The composite has an optimal microstructure of submicron matrix grains reinforced by submicron TiC0.5 particles and some nano TiC0.5 particles which were dispersed within the matrix grains. This microstructure endows the TiC0.5/Cu-Al composite with a tensile strength of 498 MPa and a tensile elongation of 10.5% at room temperature. The improved mechanical properties of the TiC0.5/Cu-Al composite are attributed to a multiple strengthening mechanism, including fine-grain strengthening, dispersion strengthening and solid-solution strengthening.