Ultrasound assisted solidification process of ternary Cu-Sn-Sb alloy

It is well-known that the application of ultrasound during liquid to solid transitions for alloys can refine the solidification microstructure and thus improves the mechanical properties. However, most published work focuses on single phase dendritic growth, whereas little has been conducted on the multiphase alloys with complicated phase transformations during solidification. In this work, the solidification process of ternary Cu₄₀Sn₄₅Sb₁₅ alloy was realized within intensive ultrasonic field with a resonant frequency of 20 kHz and ultrasound power from 0 W to 1000 W. The ultrasound refines the size of the primary ε(Cu₃Sn) intermetallic compound by two orders of magnitudes. If the ultrasound power increases to 1000 W, η(Cu₆Sn₅) phase nucleates and grows directly from parent liquid phase without the occurrence of peri-eutectic reaction on the top of the alloy sample where the ultrasound intensity is sufficiently high. These microstructural variations lead to the enhancement of compressive strength and elasticity modulus of ternary Cu₄₀Sn₄₅Sb₁₅ alloy.