DEVELOPMENT OF NEW DENTAL FUNCTIONAL TITANIUM ALLOYS

为开发新型牙科生物材料，研究了相变温度低、力学性能好的形状记忆TiPd合金。采用x射线衍射、硬度试验和拉伸试验对Ti-42.5mol%Pd和Ti-50mol%Pd合金的TiPd-Co合金进行了分析。Ti_2Pd、Ti_2Co和i.c（不适应相）相沉积在Ti-42.5mol%Pd基TiPd-Co合金中，没有形状记忆效应，但只要适当选择合金成分和热处理温度，这些相可以减少。例如，在900°C淬火的Ti-37.5mol%Pd-5mol%Co中没有出现这些相。Ti-50mol%Pd合金为基础的TiPd-Co合金在较低温度下表现出形状记忆效应。结果表明，Ti-30mol%Pd-20mol%Co合金在20C温度下仍具有形状记忆效应。由于单一的β - TiPd相，该合金应具有理想的力学性能和形状记忆效应的牙科生物材料。但TiPd-Co合金的耐蚀性不如SUS316L不锈钢。应加入一些元素来提高耐蚀性。

Shape memory TiPd alloys which has low transformation temperature and good mechanical properties was invetigated in order to develop new dental biomaterials. TiPd-Co alloys based on Ti-42.5mol%Pd and Ti-50mol%Pd alloys were analyzed by X-ray diffraction, hardnes test and tensile test. Ti_2Pd, Ti_2Co and I.C.(incommensurate) phases without a shape memory effect deposited in TiPd-Co alloys based on Ti-42.5mol%Pd alloy, but these phases could be decreased if an alloy composition and heat treatment temperature could be chosen adequately. For example, those phases did not appear in the Ti-37.5mol%Pd-5mol%Co quenched from 900ﾟC.TiPd-Co alloy based on Ti-50mol%Pd alloy showed a shape memory effect at lower temperature. It was founded that Ti-30mol%Pd-20mol%Co alloy has a shape memory effect even at 20C.Because of a single beta TiPd phase, the alloy should have desirable mechanical properties and a shape memory effect for dental biomaterials. But the corrosion resistance of the TiPd-Co alloys were inferior to that of SUS316L stainless steel. The corrosion resistance should be improved by adding some elements.