Effect of ball milling on properties of porous Ti–7.5Mo alloy for biomedical applications

Abstract Porous titanium has been used to anchor implants through bone growth into the porous structure. This bone ingrowth provides a strong implant/bone bond, and the pores may be interconnected three-dimensionally to provide enough space for the attachment and proliferation of new bone tissues and to facilitate the transport of body fluids. In the present study, porous scaffolds fabricated from three kinds of ball-milled Ti–7.5Mo alloy particles were successfully prepared through a space-holder sintering method, and the compressive strengths and moduli of all the sintered porous Ti–7.5Mo conform to the basic mechanical property requirement of cancellous bones. However, the porous Ti–7.5Mo fabricated from particles ball milled for 15 h (TM15) possesses a relatively higher strength. Moreover, the elastic modulus of TM15 is 1.72 GPa, which is comparable to that reported for cancellous bone. Furthermore, the porous TM15 alloy exhibited better apatite-forming abilities after pretreatment (with NaOH or NaOH + water) and subsequent immersion in simulated body fluid (SBF) at 37 °C. After soaking in a SBF solution for 21 days, a dense apatite layer covered the inner and outer surfaces of the pretreated porous TM15 substrates, thereby providing favorable bioactive conditions for bone bonding and growth.