Microstructural evolution and densification of Fe80P11C9 metallic glass under high pressure

The structural evolution of Fe80P11C9 metallic glass was investigated by X-ray diffraction with synchrotron radiation under high pressure up to 32 GPa at room temperature. The diffraction data, structure factor and pair distribution function show no indication of phase transition. The positions of the first sharp diffraction peak q(1) are increasing and scale with pressure. The nearest neighbour distance r(1) decreases with increasing pressure. After decompression, q(1) and r(1) do not revert to normal levels at ambient pressure. The results indicate that microstructural relaxation occurs during pressure progress. The annihilation of free volumes and reduction of voids in the amorphous matrix increase the packing density of amorphous alloys. The present study demonstrated that high pressure induces a 'highly ordered' glass state and densification of metallic glass.