High strength titanium alloys can be prepared by powder metallurgy process, but the titanium alloy still has some problems such as high elastic modulus and unsuitable pore properties for bone growth. In this paper, the biomedical porous Ti/16Mg composite material with elastic modulus close to that of human bone and strength meeting the requirements of human implants was prepared by powder metallurgy combined with microwave sintering method. The effects of particle size and addition amount of pore-making agent NH4HCO3 on microstructure, mechanical properties and corrosion resistance of the composites were investigated by scanning electron microscopy, X-ray diffraction, metallography, compression test and corrosion resistance test. The results show that NH4HCO3 has no significant effect on the phase composition of porous Ti/16Mg composites. The pore size of the sample increases with the increase of NH4HCO3 particle size, and the porosity of the sample increases from 16.64% to 33.09% with the increase of NH4HCO3 addition. When the particle size of NH4HCO3 is 165-198 μm and the addition amount is 18wt.%, the elastic modulus of the sample is 6.49 GPa and the compressive strength is 115 MPa, which can meet the mechanical property requirements of human implants. Different particle sizes of NH4HCO3 have little effect on the corrosion resistance of the composites. With the same particle size, the corrosion resistance of the composite decreases slightly and the polarization resistance decreases from 574.528Ω?cm-2 to 139.236Ω?cm-2 with the addition of NH4HCO3 increasing from 0 to 24wt.%.
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