Synthesis and mechanical behavior of in-situ porous Ti particle reinforced Mg-Cu-Gd-Ag bulk metallic glass matrix composite

The in-situ porous Ti particle reinforced Mg-based bulk metallic glass matrix composites have been successfully prepared via dealloying reaction in metallic melt. The microstructure, thermal properties and mechanical properties of the composites containing various volume fraction of porous Ti particles were investigated in detail. It is shown that with higher content of porous Ti particles, the glass-forming ability of the composites degrades gradually with the precipitation of fine crystalline phases among the glassy matrix. When the volume fraction of porous Ti particle is 26.3 vol%, the composite shows an fracture strength of 1125 MPa, 14.1 % higher than the monolithic glassy base alloy. Furthermore, the composite also exhibit an improved plastic strain of 0.94 %. The in-situ porous Ti particle and the submicron crystalline phase can hinder the rapid propagation of the main shear bands, causing the generation of multiple shear bands. It is found that abundant shear bands are formed around the porous Ti particle. The present synthesis strategy of in-situ porous reinforcing phase will contribute to the breakthrough in designing novel metal matrix composites.