Flow Velocity Affecting Dendrite Growth of Fe-C Alloy

Abstract

The phase field model coupling with the concentration field and flow field is used to simulate the dendrite growth during isothermal solidification of Fe-C alloy in a forced flow. The effects of flow velocity on the dendrite growth are studied. The results indicate that with introducing the forced flow, the upstream secondary dendrite arm space decreases, the downstream secondary dendrite arm space increases. As flow velocity increases, the side branch at the upstream regions become bulky and tilt, the side branch at the downstream regions degenerated and even disappear, the length of upstream dendrite arm increases linearly, the length of downstream dendrite arm decreases parabolically. Meanwhile, the solute concentration of upstream dendrite tip increases slowly first, then decreases, the solute concentration of downstream dendrite tip increases monotonously.