Surface tension of superheated and undercooled liquid Co-Si alloy

The surface tension of superheated and undercooled liquid Co 25 wt.% Si alloy was measured by an electromagnetic oscillating drop method. The experimental temperature regime was from 1384 to 2339 K and a maximum undercooling of 223 K (0.14 T_L) was achieved. The surface tension of liquid Co 25 wt.% Si alloy is 1.604 Nm^-1 at the liquidus temperature of 1607 K, and its temperature coefficient is -4.0 × 10^-4 Nm^-1K^-1. On the basis of previous research results of pure Co and Si, an expression is developed to predict the surface tension of binary Co-Si alloy system. The other thermophysical properties, such as the viscosity, the solute diffusion coefficient, and the density of liquid Co 25 wt.% Si alloy are also derived by the relevant theoretical models.