Ultrasound assisted casting method for fabricating B₄C_p/Al composites with the addition of K₂ZrF₆

In this research ultrasound assisted casting method was applied to fabricate 10 wt.%B₄C_p/Al composites with the addition of K₂ZrF₆. The effects of Zr content on the microstructure, including the distribution and the interface of B₄C particles, as well as the mechanical properties of composites were investigated. Experimental results showed that an interfacial layer which was composed by nano-sized ZrB₂ particles could be formed on B₄C surface, which was beneficial for improving the dispersity and hindering the decomposition of B₄C particles in the Al melt. As the addition amount of Zr satisfied the ratio of (wt.%Zr)/(wt.%B₄C) = 0.2, the B₄C_p/Al composites with a homogeneous microstructure had the best comprehensive and most stable mechanical properties.