医用多孔NiTi合金的显微组织、力学性能及耐蚀性

Microstructure, Mechanical Properties and Corrosion Resistance of the Biomedical Porous NiTi Alloy

摘要:

采用气氛烧结法制备了生物医用多孔NiTi合金，考察了造孔剂碳酸氢铵含量对合金显微结构、抗弯强度、弹性模量和耐蚀性的影响。结果表明，多孔NiTi合金主要含有NiTi合金相及少量Ti2Ni和Ni3Ti杂质相组成，碳酸氢铵含量对合金的相组成无显著影响。随着碳酸氢铵含量的增加，多孔NiTi合金的孔隙率增加、孔径增大，而抗弯强度和弹性模量降低，在模拟体液Hank’s溶液中的耐蚀性变差。多孔NiTi合金孔隙率为36%~62%，孔径为50~300 μm，抗弯强度为22~220 MPa，弹性模量为0.7~6 GPa，这些参数均与人体骨组织极为接近，说明此多孔NiTi合金是非常有前途承重硬组织替代材料

Abstract:

The biomedical porous NiTi alloy was prepared by atmosphere sintering process, and the effects of NH4HCO3 contents on the microstructure, bending strength, elastic modulus and corrosion resistance of the biomedical porous NiTi alloy were investigated. The results show that with increasing the NH4HCO3 content, the porosity and pore size of the porous NiTi alloy increase, while the bending strength, elastic modulus and corrosion resistance all decrease. The porosity of the porous NiTi alloy is about 36%~62%, the pore size 50~300 μm, the bending strength about 22~220 MPa and the elastic modulus about 0.7~6 GPa. All of these parameters are very close to that of human bones, indicating that these porous NiTi alloys could be used as the candidate of human hard tissue replacement materials