Study on Effect of Particle Size on Zr-based Amorphous Alloys Prepared by SPS

Three kinds of Zr₅₅Cu₃₀Al₁₀Ni₅ amorphous alloy powders with different particle sizes are sintered by spark plasma sintering (SPS) method, and bulk amorphous alloys are prepared. The effect of particle size on amorphous alloy prepared by SPS method is analyzed by testing properties such as density, hardness and compression strength. It is found out that density of the sintered amorphous alloy specimen decreases with the increase of powder size. In the pre-pressing stage of sintering, the densification of powders is achieved by mechanical movement and particle rearrangement, and the smaller the particle size and the closer the particles pack, the higher the densification degree. When the pulse current is applied, compare with the large sized particles, the small sized particles have larger contact area, and the heat transfers faster, which leads to higher densification degree. The hardness of the sintered specimen with particle size of 106-250 μm is the highest, that of the specimen with particle size of 15-53 μm follows, and that of the specimen with particle size of 53-106 μm is the lowest. The non-crystal partly crystallizes, promoting the hardness of the specimen with particle size of 106-250 μm efficiently. The compression strength of the specimen with particle size of 53-106 μm is the highest, that of the specimen with particle size of 106-250 μm follows, and that of the specimen with particle size of 15-53 μm is the lowest. The interface bonding force between the particles small size is weak, making the compression strength of the specimen with particle size of 15-53 μm the lowest, and the precipitation of the crystallized phase contributes to lower compression strength of the specimen with particle size of 106-250 μm than the specimen with particle size of 53-106 μm.