Microstructure and mechanical properties of particle reinforced metal matrix composites prepared by gas-solid two-phase atomization and deposition technology

In this paper, a gas-solid two-phase atomization and deposition process for high-quality particle reinforced metal matrix composites was proposed and used in the manufacture of 7055-SiCp composites specimens. The microstructure and mechanical properties of fabricated specimens were tested and then compared with conventional spray formed 7055Al alloy to evaluate the proposed technology. The average grain size of 7055-SiCp composites is about 16 μm, which is much smaller than that of 7055Al alloy (about 24 μm). The SiC particles uniformly distribute throughout the matrix, and no particle agglomeration can be observed. The compression peak stress of 7055-SiCp composites at room temperature is 687.5 MPa, and 4.74% larger than that of spray formed 7055Al alloy. Results indicate the gas-solid two-phase atomization and deposition process proposed in this paper to be a promising high-quality metal matrix composites preparation technology.