Fabrication, characterization and in vitro biocompatibility evaluation of porous Ta–Nb alloy for bone tissue engineering

•Porous Ta–Nb alloys were prepared as a novel biomaterial for the first time.•Excellent mechanical properties of the porous Ta–Nb alloy were obtained.•The mechanical properties can be tailored by adjusting the Nb content.•The excellent in vitro biocompatibility of porous Ta–Nb alloys was shown.

Porous Ta–Nb alloys were fabricated using the sponge impregnation technique and the powder metallurgy technique (P/M) in combination. All porous Ta–Nb alloys displayed interconnected open cell structures with porosities around 64% and pore sizes in the range of 300–500 μm. No carbide, oxide, or intermetallic-related phases were detected by the X-ray diffraction (XRD). Porous Ta–Nb alloys displayed sintering neck growth, smoother surface of the particles and more shrinkage of the micropores, with Nb contents increasing from 5% to 15%. The compressive strength and Young's modulus of the Ta–Nb alloys agreed well with the requirements of trabecular bone. The normalized compressive plateau stress and Young's modulus increased from 52.27 MPa to 85.43 MPa and from 1.850 GPa to 2.540 GPa, respectively, with Nb contents increasing from 5% to 15%. Porous Ta–Nb alloys had no cytotoxicity and possessed the excellent biocompatibility similar to porous Ta scaffolds.