Structural and mechanical properties of CuZr/AlN nanocomposites

Powder metallurgy method was used to prepare copper alloy nanocomposites (CuZr/AlN) with high strength and conductivity. Optical microscopy, high-resolution transmission electron microscopy and other methods were adopted to study the impact of different sintering technologies on the structural and mechanical properties as well as the impact of solution and aging treatments on the mechanical properties of CuZr/AlN. The result shows that the specimen has a dense structure, and the size of the crystal grain is around 0.2 µm. The Brinell hardness of the specimen increases with the increase in re-pressing pressure and sintering temperature. The Brinell hardness of specimen also increases with the increase in zirconium content. However, above 0.5% (mass fraction) of zirconium content, the Brinell hardness of the nanocomposites is reduced. The buckling strength of the specimens increases with the increase in re-pressing pressure and sintering temperature. The buckling strength is the highest when the zirconium content is 0.5%. The Brinell hardness is lower after solution and aging treatments at 900 °C. The Brinell hardness of the CuZr/AlN series specimen after the aging treatment at 500 °C or 600 °C increases. The specimen was also over aged at 700 °C.