Effects of some Parameters on Properties of Cu-Al<sub>2</sub>O<sub>3</sub> Composite Materials Synthesized by Internal Oxidation Process

Abstract

The Cu-Al2O3 composite materials applying for electrode materials were successfully synthesized by internal oxidation process. The process included steps: producing solid solution α-Cu[Al] and oxidizing completely solid solution α-Cu[Al] as powders, then adding pure Cu powders and mixing in planetary ball milling, the mixtures were compressed into cylindrical samples, reduced at 750°C in 3h and sintered at 950°C in 2h in reduction atmosphere. The XRD patterns showed that total Al in Cu-matrix were completely oxidized in range of 20¸25h. After reducing and sintering process, the final products were Cu-Al2O3 composite materials. The results showed that micro-hardness, porosity and compress strength of Cu-Al2O3 materials increased with increasing of Al2O3 content, which was the result of dispersion of the fined Al2O3 grains in Cu-matrix. When Al2O3 content was unchanged, the porosity of received materials decreased with increasing of compress pressure. Whereas, the electrical conductivity of Cu-Al2O3 composite materials decreased comparing with pure Cu and it decreased with increasing of Al2O3 content.