功率超声对铝合金熔体细化机理的研究

Research on Effect of Power Ultrasound on Refinement Mechanism of Aluminum Alloy Melt

采用无保护和有保护套管两种结构的超声不锈钢工具头,在相同实验条件下作用于Al-5%Si合金熔体,研究了功率超声对其凝固过程的细化机理。结果表明,经功率超声后晶粒均得到细化,但细化效果有差异,其原因在于功率超声对晶粒的细化作用有空化效应和声流效应,此外,工具头中Fe原子进入熔体对晶粒细化起到异质形核作用。

The refinement mechanism in solidification process was studied using ultrasonic stainless steel probe with and without protective casing to act on Al-5%Si alloy underthe same conditions.The results indicate that all the grains refine,but the refinement effect is different.The reason is that besides the cavitation and acoustic streaming effects,Fe in stainless steel fuses into alloy melt,which plays a role in the heterogeneity nucleation.