Enhanced compressive strengths of lamellar porous titanium scaffolds with in-situ generated carbide fiber-bridged structure

Abstract

Directional lamellar porous titanium scaffolds have an anisotropic pore structure, which has a high compressive strength in a single direction due to the buckling deformation of the lamellar pore walls. However, the weak bond between the pore walls easily leads to splitting, resulting in the insufficient mechanical stability of porous titanium scaffolds. Porous titanium scaffolds with a directional straight-through structure were fabricated in this study by directional freeze casting combined with TiH 2 in-situ reduction reaction, and short carbon fibers were introduced to form a fiber-bridge structure between the lamellar pore walls. TiC/Ti fibers were formed by diffusion and the in-situ reaction of carbon and titanium atoms. The fiber bridging density increased with the short carbon fiber contents. Interlayer splitting due to compressive stress can be prevented, and the compressive strength can be improved by constraining the buckling deformation of pore walls. The maximum compressive strength of fiber-bridged porous titanium scaffolds was 161.66 MPa, which is 36 % higher than that of pure porous titanium scaffolds. Fabricated scaffolds can be applied in the field of bone implant materials due to their low biotoxicity and biocompatibility. • Porous titanium scaffolds with carbide fiber-bridged structure were fabricated. • Interlayer splitting due to compressive stress can be prevented. • The compressive strength was improved by constraining the buckling deformation. • The enhanced mechanism of fiber-bridged structure was discussed.