Scalable manufacturing of the Al-based master composites containing TiB2 and TiC particles and their modification effect on the hot cracking of rapidly solidified Al alloys

Abstract

This work proposed a scalable manufacturing method for preparing the Al-based master composites containing micrometer-TiB2 and nanometer-TiC particles through molten salt reaction combined with vibration assisted dispersion. The modification effect of the Al-based master composites on the hot cracking and microstructure of 6000 and 7000 series Al alloys with high crack sensitivity during rapid solidification is initially investigated. The results show that the addition of the mixed particles could significantly refine the grains, effectively suppress the hot cracks, and improve the mechanical properties of rapidly solidified Al alloys. Meanwhile, the modification effect of the mixed particles is better than those of the single-phased micrometer-TiB2 particles or nanometer-TiC particles. This scalable and low-cost manufacturing process provides a practical way for preparation of metal matrix composites with low concentration of particles, and proposed a new path to solve the hot cracking problems in the rapid solidification areas such as additive manufacturing.