The effect of oscillatory flow on nucleation and grain growth in the undercooled melt

Abstract The present paper investigates the effect of the oscillatory flow induced by vibration on nucleation and grain growth in the undercooled melt in terms of the analytical method. The analytical solution shows that the oscillatory flow stimulates the meta-stable crystalline embryos to grow rapidly and facilitates to form a great number of nuclei in the undercooled melt during the initial stage of nucleation. As a grain grows, the oscillatory flow alternately facilitates and inhibits the growth of the grain such that the formed nuclei survive. For the low frequency and low acceleration, the interface temperature of a grain rises rapidly immediately after nucleation and then gradually decreases. For the high frequency, the interface temperature shows no significant difference with the increase of frequency. For the high acceleration, the interface temperature oscillates with the oscillatory flow. The oscillation acts as a stimulating and inhibitory effect and facilitates to produce a number of crystalline sites in the undercooled melt. The grains are refined with increasing vibration acceleration under a certain vibration frequency.