激光多次熔凝Zr₅₅Cu₃₀Al₁₀Ni₅非晶合金的晶化形态与演化机理

Laser additive manufacturing technology is a feasible technology for the fabrication of bulk metallic glass with complex geometry. It has the characteristics of small molten pool and high cooling rate. However, crystallization often occurs in heat affected zone (HAZ). In this work, laser multiple remelting of Zr₅₅Cu₃₀Al₁₀Ni₅ metallic glass by pulsed laser was carried out and the morphological evolution of the HAZ crystalline phase in the multiple remelting process was studied. The results show that with the increase of the remelting times, the crystalline grains number and size are both improved. With the growth of the grains, the crystallization caused by the growth of the crystalline grains in the molten pool also becomes more and more remarkable. Both the size and number of the grains in the HAZ increase linearly with the increase of the remelting times. The nucleation rate and growth rate of different metallic glass plates are close, whereas the initial crystalline grains number and size are different, which are attributed to the different cooling process in the copper casting of the metallic glass plates.