Crystallization prediction on laser three-dimensional printing of Zr-based bulk metallic glass

Laser three-dimensional (3D) printing technology provides an opportunity to fabricate metallic glasses without any dimensional constraint. However, the crystallization, which has tremendous effect on the mechanical and chemical properties of bulk metallic glasses (BMGs), is hard to be avoided in the printing process. Thus, it's especially important and necessary to propose an effective method for crystallization prediction on laser 3D printing of BMGs. In the present paper, the crystallization of a Zr-based BMG during laser 3D printing process was analyzed based on the estimated time-temperature-transformation (TTT) diagrams and thermal cycle curves obtained from finite element method (FEM) analysis. The spatial distributions of crystallization calculated by our method consistent well with the experimental observations, indicating that the method combining the TTT diagrams and FEM simulation of thermal cycle curves provide a reliable way to predict the crystallization of BMGs during laser 3D printing process, which is beneficial to optimize the printing process and guide the laser 3D printing of BMGs.