Ultrahigh strength CuCr/diamond composites fabricated by powder metallurgy

CuCr/Diamond (Dia) composites were fabricated by high-energy ball milling and rapid hot-press sintering. The studied CuCr/Dia composites exhibited excellent mechanical properties, reaching a hardness of 187 HV, an ultimate tensile strength of 1010 MPa. In-situ transition layers of Cr3C2 and Cr23C6, ranging between 10 and 30 nm, were generated at the Cu/diamond interface. This transition layers significantly enhanced the bonding strength between the diamond and the Cu matrix. The load could be effectively transfer to the diamond particle due to the strong bonding. Additionally, nanoscale sub-structures in the matrix can enhance the composite's strength. The studied composite displayed superior strength compared to other copper matrix composites. These findings could extend the applications of the copper-based composites with ultrahigh strength.