| 摘要: |
| 采用放电等离子烧结技术制备表面多孔Ti-Ag /NiTi梯度合金，研究了不同Ag含量对梯度合金微观组织、界面结合、表面孔隙特征、力学性能、体外生物活性及抗菌性能的影响及机理。结果表明：梯度合金中间基体主要由奥氏体NiTi 相(B2)和单斜马氏体NiTi 相(B19")组成，同时还存在少量次生相Ti2Ni相，表面多孔层主要由α-Ti、TiAg和Ti2Ag相组成，内外层界面形成稳定冶金结合；Ag含量增加对梯度合金表面孔隙率和平均孔径影响不大，但抗压强度值提高而弹性模量变化不明显，这主要与表面多孔层中TiAg和Ti2Ag相的强化作用有关；梯度合金在人工模拟体液中浸泡14天后表面形成了大量类骨磷灰石层，显示了优异的体外生物活性，同时Ag的加入显著提高了梯度合金的抗菌性能。 |
| 关键词: NiTi梯度合金 放电等离子烧结 微观组织 力学性能 抗菌性能 |
| DOI：10.11951/j.issn.1005-0299.20180081 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目(31660262). |
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| Effect of Ag contents on microstructure and properties of surface porous Ti-Ag / NiTi gradient alloy |
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DENG Xia, HE Yuanhuai, JIAO Meiqi, ZHANG Yuqin, JIANG Ye-hua
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School of Materials Science and Engineering,Kunming University of Science and Technology
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| Abstract: |
| surface porous Ti-Ag/NiTi gradient alloy was fabricated by spark plasma sintering (SPS) technology. The effects of different Ag contents on microstructure, interface bonding, surface pore characteristics, mechanical properties, in vitro biological activity and antibacterial property of the alloy were investigated. The results showed that the matrix of the gradient alloys are mainly consisted of NiTi phase and a few complex phases ofTi2Ni, and the surface porous layers are mainly consisted of a-Ti, TiAg and Ti2Ag phases. Furthermore, we can observe a stable metallurgical bonding on the internal and external interface of the gradient alloy. With increasing of Ag contents, the porosity and average pore size of surface porous layer do not vary significantly, but compressive strength of the alloy increase and the compressive elastic modulus shows no obvious change, which is mainly related to the strengthening of TiAg and Ti2Ag phases in the surface porous layer. Furthermore, a lot of bone-like apatite is deposited on the surface of gradient alloy after soaking in SBF for 14 d and showing excellent in vitro biological activity. Meanwhile, the addition of Ag significantly improves the antibacterial properties of the gradient alloy. |
| Key words: NiTi gradient alloy spark plasma sintering microstructure mechanical properties antibacterial property |
