An efficient approach to endow TiNbTaZr implant with osteogenic differentiation and antibacterial activity in vitro

•Grain refinement and TiZn2 intermetallic complex were found in the stir zone.•Dislocation and α″ martensite enhanced the microhardness of the composite surface.•The composite surface promoted cell adhesion, proliferation and osteogenic differentiation.•The composite surface inhibited bacterial adhesion and growth.