• 공업화학
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• 제3권1호
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• pp.88-99
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• 1992

광 전기분해시 양극으로 사용되는 산화티타늄 반도체 전극의 안정성을 증대시키고 효율향상을 위해서 순수한 티타늄 전극을 양극 산화법, 전기로 산화법, 불꽃 산화법으로 산화 피막을 제조하였으며 In을 Ti와 $TiO_2$소지에 전기도금을 한 후 전기로 산화법으로 혼합 산화물을 제조하였다. 또한 $Al_2O_3$ 와 NiO는 진공증착 방법을 이용하여 Ti 소지위에 증착시킨 후 전기로 산화법을 이용하여 혼합 산화물을 제조하였다. 에너지변환 효율(${\eta}$)은 인가전위에 따라서 다른 값을 갖는데 0.6V로 계산하여 보면 $1200^{\circ}C$의 불꽃으로 2분간 산화시킨 전극이 0.98%로 가장 큰 값을 가졌으며 양극 산화법으로 제조한 전극의 ${\eta}$는 0.14%로 작은 값을 보여 주었다. 한편 $800^{\circ}C$ 전기로에서 10분간 산화시킨 전극의 ${\eta}$는 0.57%로 띠간 에너지는 2.9eV로 나타났다. 한편 In을 Ti 및 $TiO_2$ 소지위에 전기도금시킨 전극의 ${\eta}$는 0.8%였으며 인가전위가 증가함에 따라서 ${\eta}$는 증가하였다. 그러나 $Al_2O_3$와 NiO를 Ti소지위에 진공증착시킨 전극의 ${\eta}$는 다른 전극들에 비해서 가장 낮은 값을 나타내었다.

• 대한치과보철학회지
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• 제31권3호
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• pp.423-446
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• 1993

Titanium and its alloys are finding increasing use in medical devices and dental implants. The strong selling point of titanium is its resistance to the highly corrosive body fluids in which an implant must survive. This corrosion resistance is due to a tenacious passive oxide or film which exists on the metal's surface and renders it passive. Potentiodynamic polarization measurement is one of the most commonly used electro-chemical methods that have been applied to measure corrosion rates. And the potentiodynamic polarization test supplies detailed information such as open circuit, rupture, and passivation potential. Furthermore, it indicates the passive range and sensitivity to pitting corrosion. This study was designed to compare the corrosion resistance of the commonly used dental implant materials such as CP Ti, Ti-6A1-4V, Co-Cr-Mo alloy, and 316L stainless steel. And the effects of galvanic couples between titanium and the dental alloys were assessed for their useful-ness-as. materials for superstructure. The working electrode is the specimen , the reference electrode is a saturated calomel electrode (SCE), and the counter electrode is made of carbon. In $N_2-saturated$ 0.9% NaCl solutions, the potential scanning was performed starting from -800mV (SCE) and the scan rate was 1 mV/sec. At least three different polarization measurements were carried out for each material on separate specimen. The galvanic corrosion measurements were conducted in the zero-shunt ammeter with an implant supraconstruction surface ratio of 1:1. The contact current density was recorded over a 24-hour period. The results were as follows : 1. In potential-time curve, all specimens became increasingly more noble after immersion in the test solution and reached between -70mV and 50mV (SCE) respectively after 12 hours. 2. The Ti and Ti alloy in the saline solution were most resistant to corrosion. They showed the typical passive behavior which was exhibited over the entire experimental range. Therefore no breakdown potentials were observed. 3. Comparing the rupture potentials, Ti and Ti alloy had the high(:st value (because their break-down potentials were not observed in this study potential range ) followed by Co-Cr-Mo alloy and stainless steel (316L). So , the corrosion resistance of titanium was cecellent, Co-Cr-Mo alloy slightly inferior and stainless steel (316L) much less. 4. The contact current density sinks faster than any other galvanic couple in the case of Ti/gold alloy. 5. Ag-Pd alloy coupled with Ti yielded high current density in the early stage. Furthermore, Ti became anodic. 6. Ti/Ni-Cr alloy showed a relatively high galvanic current and a tendency to increase.