Fracture toughness and surface morphology of Al₂O₃/Pt composites

다국어 초록 (Multilingual Abstract)

In the present study, Al<SUB>2</SUB>O<SUB>3</SUB>-based composites with dispersed Pt particles were prepared by using a reduction-precipitation method. Particle distribution, fracture toughness, and morphology of the prepared Al<SUB>2</SUB>O<SUB>3</SUB>/Pt composites were studied. Crystal structure of the composites was evaluated by analyzing Pt characteristic peaks in the X-ray diffraction spectra. Transmission electron microscopy images indicated that the Pt particles were uniformly dispersed in the Al<SUB>2</SUB>O<SUB>3</SUB> powder. The fracture toughness of the Al<SUB>2</SUB>O<SUB>3</SUB> matrix was improved by the addition of Pt particles, since these particles effectively resisted crack propagation in the Al<SUB>2</SUB>O<SUB>3</SUB>/Pt composites. Scanning electron microscopy images indicated that the fracture of the composites followed an intergranular mechanism, typical of ceramic materials, at low Pt content, whereas a transgranular mechanism occurred at high Pt content.