Development of Fe-based bulk metallic glasses as potential biomaterials

A new series of Fe80-x-yCrxMoyP13C7 (x = 10, y = 10; x = 20, y = 5; x = 2 0, y = 10, all in at.%) bulk metallic glasses (BMGs) with the maximum diameter of 6mm have been developed for biomedical implant application by the combination method of fluxing treatment and J-quenching technique. The corrosion performance of the present Fe-based BMGs is investigated in both Hank's solution (pH = 7.4) and artificial saliva solution (pH = 6.3) at 37 °C by electrochemical measurements. The result indicates that the corrosion resistance of the present Fe-based BMGs in the above two simulated body solutions is much better than that of biomedical 316 L stainless steel (316 L SS), and approaching that of Ti6Al4V biomedical alloy (TC4). The concentrations of Fe, Ni and Cr ions released into the Hank's solution and artificial saliva solution from the present Fe-based BMGs after potentiodynamic polarization are significant lower than that released from 316 L SS. The biocompatibility of the present Fe-based BMGs is evaluated through the in vitro test of NIH3T3 cells culture in the present Fe-based BMG extraction media for 1, 3 and 5 days. The result indicates that the present Fe-based BMGs exhibit no cytotoxicity to NIH3T3 cells. And the test result of the cell adhesion and growth on the surface of the samples indicates that the present Fe-based BMGs exhibit the better cell viability compared with 316 L SS and TC4 biomedical alloys. The present Fe-based BMGs, especially Fe55Cr20Mo5P13C7 BMG, exhibit good glass formation ability, the high corrosion resistance and excellent biocompatibility, suggesting their promising potential as biomaterials.