Microstructure and mechanical properties of CU-based amorphous alloy/ copper composites consolidated by spark plasma sintering

Microstructure and mechanical properties of Cu-based amorphous alloy/ copper composites consolidated by spark plasma sintering (SPS) equipment were investigated in this study. Amorphous alloy powders were mixed with 10 to 40 vol pct of pure Cu powders and were consolidated at 460 °C for 0.5 minute under 300 or 700 MPa. The consolidated composites contained Cu particles homogeneously distributed in the amorphous matrix, and showed a considerable plastic strain, whereas their compressive strength was lower than that of the monolithic amorphous alloys. The compressive strength and plastic strain of the composites consolidated under 700 MPa showed 10 to 20 pct and 2 times increases, respectively, over those of the composites consolidated under 300 MPa. The increase in consolidation pressure could play a role in sufficient bonding between prior amorphous powders, in preventing micropores, and in suppressing the crystallization, thereby leading to the successful consolidation of the high-quality composites. These findings suggested that the composites consolidated by the SPS presented new possibilities of application to structural materials or parts requiring excellent mechanical properties and large sizes.