Preparation of ZrO₂/Cu composite by internal-oxidation

Cu-0.6%Zr (mass fraction) alloy powders were prepared by using high-pressure water atomization with non-vacuum melting, and ZrO₂/Cu in-situ reinforced composite was prepared after particle size separation, following by low-temperature oxidation, N₂+5%H₂ (volume fraction) mixture reduction and vacuum spark plasma sintering(SPS) forming. The results show that lower temperature leads to lower oxidation rate, while higher temperature leads to over oxidation and agglomeration, and the ideal oxidation parameter is 230℃×1 h; In N₂+5%H₂ gas flow of 200 mL/min, the best reduction parameter is 250℃×1 h which is measured by hydrogen-annealed experiment; Under the condition of 30 MPa, 850℃×2 h vacuum SPS, the typical performance of the ZrO₂/Cu sample has been obtained that the conductivity is higher than 83% IACS(international annealed copper standard), the hardness is higher than HB 75 and the softening temperature is 900℃.