| Ti-35Nb-7Zr-5Ta (Ti-Osteum) alloy is a new P-type of biomedical titanium alloy, with good biocompatible (no toxic elements), lower elastic modulus and high tensile strength, which can be used as one of human hard tissue implant materials and alternative ideal implant material used in the human body carries a large part, become an ideal choice of materials for human hard tissue implant and replacement. The alloy sintered by SPS can improve the problem of the uneven microstructure, and there is a certain corrosion behavior when Ti-Osteum alloys implanting in human body fluids, which can cause serious physical harm and damage to the implant in the human body. thus, there is a further study of the corrosion resistance of Ti-Osteum in human body fluids.In this study, Ti-Osteum alloys were fabricated by SPS method. The effect of sintering temperature, and different simulation artificial humoral media on the alloy electric chemical corrosion behavior are studied, and use TA1 and TC4 in Hank’s simulation artificial body fluid As contrast research, then through heat treatment improved alloy of plasticity, the effect of solution temperature and aging temperature on alloy of micro microstructure and mechanical properties of Ti-Osteum alloys, And discussed the effect of heat treatment on electrochemical corrosion properties of alloys and mechanism, Results were shown as follows:Ti-Osteum alloys with different sintering temperature have similar electrochemical behaviors, the alloy of 1150℃ with minimum corrosion current density and the passivation current density and the maximum polarization resistance, make the best Corrosion property in Hank’s simulated artificial body fluid. Compared with the TA1 and TC4, the electrochemical corrosion resistance of three materials were:Ti-Osteum>TC4>TA1. The main factors of the excellent corrosion resistance of Ti-Osteum alloy by SPS in simulated artificial body fluid were attributed to P-type single phase microstructure and a stable protective composite oxide passive film mainly consisted of TiO2, Nb2O5, ZrO2 and Ta2O5 on its surface. Ti-Osteum alloy prepared by SPS have good electrochemical corrosion properties in Hank’s, Ringer’s and 0.9% NaCl. Thus, Ti-Osteum alloy can satisfy the requirements of different medias, have advantage for the application in the human body as materials for implantation.Ti-Osteum alloy prepared by SPS after solution treatment generates a small amount of a-Ti phase and quenched martensite a"phase. After aging treatment, the primary alpha phase disappears, alloy matrix beta phase precipitates within a large number of fine acicular secondary α’ phase. Along with the increasing aging temperature, secondary α’ phase size increases. With the solution treatment temperature increases, the Ti-Osteum alloy sintered by SPS have a more uniform β-Ti structure, thus the compressive strength and yield strength decrease, the ductility is impoved. After aging, strength reduction, yield ratio lower, ductility once again raised, the compression modulus range of alloy is between 46-52Gpa and the value is near the sintered Ti-Osteum alloys.With the increase of the solution temperature, β-Ti structure is more uniform, the composite oxide film consist of TiO2, Nb2O5, ZrO2 and Ta2O5 is more evenly distributed, and the alloys corrosion performance enhanced. Solution heat treatment on Ti-Osteum alloy improved uniformity of microstructure, and corrosion-resistant performance enhanced; after aging solution, there are morea phase precipitation in alloys, and reduced the alloy corrosion-resistant, but the alloy after high-temperature aging have better corrosion resistance than sintered alloy.
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