Simulation for the Effect of Wetting Conditions of Melt Puddle on the Fe-Si-B Ribbon Alloy in the Planar-Flow Melt-Spinning Process

The wetting effect of melt puddle between nozzle and chilling wheel in the planar-flow melt-spinning process was simulated numerically. A two-dimensional model was developed for the puddle in which the inertial force, viscosity, surface tension, wettability, and heat transfer with phase transformation were incorporated. The wetting conditions include the static contact angle between the puddle and nozzle and the dynamic contact angle between the puddle and chill wheel, and their influence on the puddle shape, ribbon thickness and air-pocket frequency were evaluated. Results show that the puddle shape was affected significantly by the wetting condition on the nozzle surface rather than that on the wheel surface. The contact condition between the puddle and nozzle must be non-wetting in order to reach a steady puddle shape rapidly. On the other hand, a wetting contact condition is preferable between the puddle and wheel surface to reduce the amount of air entrainment and lower the air-pocket frequency on the ribbon surface.