Fabrication and Characterization of In Situ Zn-TiB₂ Nanocomposite

Zinc (Zn) matrix composite has been newly discovered categories of biodegradable materials. With a combination of chemical stability, thermal stability and biocompatibility, ceramic nanoparticles outperformed intermetallics of zinc alloys with inherent advantages of retaining a proper corrosion rate and an exceptional ductility. Compared with Zn alloys, Zn matrix nanocomposites showed an unprecedented strengthening without sacrifices of corrosion rate, which were introduced by intermetallics. In this work, in situ titanium diboride (TiB₂) reinforced Zn nanocomposite was prepared via a few cost-effective and economical methods: flux-assisted synthesis (FAS), ultrasound-assisted nanoparticle homogenization and hot rolling. 3 vol.% of TiB₂ nanoparticles were synthesized with an average size of 454nm, followed by molten salt assisted ultrasound homogenization and hot rolling. Hot-rolled (HR) Zn-TiB₂ performed high strength and high ductility, mostly due to precipitation strengthening (Orowan strengthening). Yield stress (YS) and ultimate tensile stress (UTS) increased by 90% and 45%, respectively, while the elongation to failure retained 23%. The mechanical performance of Zn-TiB₂ made it promise to serve as an innovative biodegradable material for load-bearing applications.