Porous Ni-Ti alloy prepared by gel-casting

Abstract:

Porous Ni-Ti alloys are widely used in biomedical implant material because of its shape memory effect. In this work, porous Ni-Ti alloy with large size and complicated shape was fabricated by gel-casting of TiH2 powder and atomization nickel powder, followed by vacuum drying, thermal debinding and subsequent vacuum sintering process. Effects of sintering temperature on porosity, mechanical properties, phase composition and microstructure of porous Ni-Ti alloys were studied by XRD and SEM. With the increase of sintering temperature, the porosity of Ni-Ti alloy reduces while the compression strength and Young’s modulus increases. Under the condition of vacuum sintering at 1050 ℃ for 2h, the obtained samples with the solid loading of 45vol. % exhibits a porosity of 42.65%, compression strength of 202.65 MPa and Young’s modulus of 17.14 GPa, which match the demands of human bones.