Summary: | 碩士 === 國立臺灣科技大學 === 機械工程系 === 106 === The high corrosion resistant property of biomedical grade titanium alloys is commonly accepted. However, there are some reports indicated that titanium tends to accumulate in surrounding tissues due to dissolution and release of metallic ions in vivo. The use of Ti-based implants always brings out these concerns. Metallic ions such as Al, Zr and V would cause the undesirable reactions and excessive tissue degradation. On the other hand, the bonding between titanium surface and living bone tissue is very weak results in longer healing period.
As one of the novel technologies in surface treatment field, micro–arc oxidation process is capable to produce oxide layers on surface of valve metal including magnesium, aluminum, titanium, etc., which improves the wear and corrosion resistant properties of metal. Porous oxide layers containing calcium and phosphorus were fabricated on titanium surface in this research. The object is to observe the physical, chemical and corrosion resistant properties of these porous oxide layers. The difference of surface morphology, layer thickness and corrosion resistance between various samples are examined by SEM, XRD, EDS and polarization curve.
The result shows that the thickness, pore size and hardness increased by extending the process time. The observation by EDS and Mapping indicate that the amount and distribution of calcium and phosphorus ions were improved. Surface morphology and density of oxide layers are also important factor to affect corrosion resistance.
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