烧结温度对凝胶注模多孔Ni-Ti合金性能的影响

Effect of Sintering Temperature on Properties of Porous Ni-Ti Alloy Prepared by Gel-Casting

以TiH_2粉及雾化Ni粉为原料,采用凝胶注模成型技术,制备出Ni-Ti凝胶生坯,再通过真空干燥、脱脂以及烧结工艺制备出多孔Ni-Ti合金。运用XRD、SEM对多孔Ni-Ti合金进行了相成分及微观结构表征,分析了不同烧结温度对于多孔Ni-Ti合金孔隙率、力学性能、物相成分及微观形貌的影响。结果表明,随着烧结温度的增加,孔隙率降低,抗压强度和杨氏模量增加。对固相体积分数为45%的生坯,在1050℃下高真空烧结2 h,制备出孔隙率为42.65%,抗压强度为202.65 MPa,杨氏模量为17.14 GPa,主相为NiTi相的多孔Ni-Ti合金。基体满足人体骨性能需要。

Porous Ni-Ti alloy with large size and complicated shape was fabricated by gel-casting of Ti H2 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 morphology of porous Ni-Ti alloys were studied by XRD and SEM.With the increase of sintering temperature,the porosity of Ni-Ti alloy declines while the compression strength and Young＇s modulus increase.Under the condition of vacuum sintering at 1050 °C for 2 h,the obtained samples from the green compact with the solid loading of 45% exhibit a porosity of 42.65%,compression strength of 202.65 MPa,Young＇s modulus of 17.14 GPa and Ni Ti main phase,which satisfy the demands of human bones.