Two-dimensional phase-field study for spangle texture formation in hot-dip galvanizing

Abstract The surface of a hot-dip galvanized layer is characterized by a beautiful solidification pattern of large Zn grains with a {0001} texture, which is called the spangle. The formation mechanism for the {0001} spangle texture has not yet been conclusively clarified. In this study, dendrite growth in a thin coating layer with Zn-0.2 wt%Al was systematically simulated in two dimensions using the phase-field method. As a result of the simulations, the {0001} texture is not formed when considering only the anisotropy of the solid–liquid interface energy. On the other hand, when considering the anisotropy of mobility, a clear {0001} texture is observed. Thus, it is concluded that the formation of the {0001} spangle texture may result from mobility anisotropy.