基于压铸锌合金锭生产的晶粒细化方式研究OA

This paper systematically investigates the effects of cooling rate control,ultrasonic treatment during solidification,and the addition of self-inoculants before pouring on grain refinement in the production process of die-cast zinc alloy ingots.The results demonstrate that:(1)Maintaining a solidification cooling rate of approximately 1.0℃/s at a pouring temperature of～500℃effectively refines primary η-phase grains while avoiding the formation of a petal-like morphology caused by excessively high cooling rates.(2)Applying longitudinal ultrasonic waves at 20 kHz during solidification significantly refines primary η-phase grains(resulting in a fine equiaxed morphology),promotes the formation of a regular lamellar structure in the eutectic phase,substantially enhances the overall microstructural homogeneity of the ingot,and alleviates compositional segregation induced by solidification sequence variations.(3)Adding an appropriate amount(0.5%-1.0%)of the same grade zinc alloy as a self-inoculant prior to pouring markedly increases the nucleation rate,achieving further grain refinement without introducing heterogeneous particles.This study provides a feasible technological pathway for optimizing grain refinement in the industrial production of die-cast zinc alloy ingots.