Crystallization behavior of annealed Zr₅₅Cu₃₀Al₁₀Ni₅ bulk metallic glass during pulsed laser remelting

The crystallization behavior of annealed metallic glasses during pulsed laser remelting was investigated in this work. The as-casted Zr₅₅Cu₃₀Al₁₀Ni₅ bulk metallic glasses were annealed at 390, 430, 530, 792 and 902°C separately. And then these annealed alloys were remelted by pulsed laser. The experiment results show that the alloys annealed at 390 and 430°C were still metallic glasses, and their crystallization behavior during remelting is similar to the remelting of metallic glass without annealing treatment. The specimens annealed at 530, 792 and 902°C were completely crystallized. After remelting, the molten pools of these specimens were amorphous. For the specimens annealed at 530 and 792°C, there was no obvious epitaxial growth at the bottom of molten pools. For the specimens annealed at 902°C, there was little primary phase epitaxial growth at bottom of molten pool after one time laser remelting while without epitaxial growth after 11 times laser remelting. The epitaxial growth was caused by the area reserved the composition distribution of CuZr₂ primary phase during laser remelting. So it is hard to obtain epitaxial growth during laser remelting for Zr₅₅Cu₃₀Al₁₀Ni₅ a crystallization substrate because of the slow diffusion. So it is easy to keep molten pool as amorphous state during laser treating Zr₅₅Cu₃₀Al₁₀Ni₅ bulk metallic glasses.