Facile fabrication of nanoporous structure on β titanium alloy to eliminate stress shielding for bone implant

A TiNb nanoporous structure on the surface of Ti2448 (Ti24Nb4Zr8Sn, wt. %) alloy substrate was successfully fabricated by a combination method of magnetron sputtering and chemical dealloying. Such a nanoporous structure has the characteristics of bicontinuous opening. The elastic modulus of the obtained nanoporous film reached 24 GPa, which is consistent with the elastic modulus of human bone (10–30 GPa). Such a nanoporous structure reduces the modulus of the surface while ensuring the high strength of the alloy. It will effectively eliminate the stress shielding effect of the bone on the implant. This method has promising applications in the surface modification of titanium implants to enhance osseointegration.