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Zn-xNb (x=0, 0.5, 1, 3, 5, 10%) composites were prepared by vacuum heating-press sintering process with Zn and Nb powders as raw materials. The surface morphology and phases of the composites were characterized. The effects of Nb addition on the mechanical properties, corrosion degradation behavior, and cytocompatibility of the composites were investigated. The results show that the Nb particles are distributed in the Zn matrix in a lamellar shape. With the increase of Nb content, the compressive yield strength of the composite increases first and then decreases, and Zn-0.5Nb shows the best performance. The increase of Nb content accelerates the degradation of the composites. Compared with pure Zn, the samples with high Nb content show better cytocompatibility, probably owing to the addition of Nb reducing the release of Zn2+.

Repair of bone defects remains a major challenge in the field of orthopedics. Biodegradable zinc (Zn) has been considered as a revolutionary material for bone repair. However, it exhibits relatively poor mechanical strength and cytocompatibility as well as slow degradation rate, hindering its potential application as bone repair material. In the present work, biodegradable Zn-1 wt%Mg-nvol%β-TCP (n = 0, 1, 3, 5, 10) composites are fabricated via vacuum heating-press sintering to address the above concerns. The results show that the addition of magnesium (Mg) and beta-tricalcium phosphate (β-TCP) positively regulate the mechanical properties, degradation properties, and osteogenic activity of the composites. Zn-1 wt%Mg-3 vol%β-TCP possess the highest compressive yield strength of approximately 243.9 MPa compared with about 137.6 MPa of pure Zn. The in vitro corrosion rates of the Zn-1Mg-β-TCP composites are tunable between 0.428 and 0.546 mm/y. The 24-week in vivo experiments prove that the Zn-1Mg-β-TCP composites possess better osteogenic activity than that of pure Zn. In general, the Zn-1Mg-β-TCP composites exhibit suitable mechanical strength and degradation rate, coupled with their great biological activity, which are expected to provide reliable performance for clinical bone repair.