치과용 주조합금의 주조방법에 따른 부식거동

Corrosion Behavior of Dental Alloys Cast by Various Casting Methods

  • 최한철 (조선대학교 치과대학 치과재료학교실 및 생체재료나노계면활성화센터) ;
  • 고영무 (조선대학교 치과대학 치과재료학교실 및 생체재료나노계면활성화센터)
  • 발행 : 2004.10.01

초록

The defects of partial denture frameworks are mainly shrinkage porosity, inclusions, micro-crack, particles from investment, and dendritic structure. In order to investigate a good casting condition of partial denture frameworks, the three casting alloys and casting methods were used and detected casting defects were analyzed by using electrochemical methods. Three casting alloys (63Co-27Cr-5.5Mo, 63Ni-16Cr, 63Co-30Cr-5Mo) were prepared for fabricating partial denture frameworks with various casting methods; centrifugal casting (Kerr, USA), high frequency induction casting (Jelenko Eagle, USA), vacuum pressure casting (Bego, Germany). The casting temperature was $1,380^{\circ}C$ (63Co-27Cr-5.5Mo and 63Ni-16Cr) and $1,420^{\circ}C$ (63Co-30Cr-5Mo). The casting morphologies were analyzed using FE-SEM and EDX. The corrosion test of the dendritic structure was performed through potentiodynamic method in 0.9% NaCl solutions at $36.5^{\circ}C$ and corrosion surface was observed using SEM. The defects of partial denture frameworks improved in the order of centrifugal casting, high frequency induction casting, and vacuum pressure casting method, especially, pore defects were found at part of clasp in the case of centrifugal casting method. The structure of casting showed dendritic structure for three casting alloys. In the 63Co-27Cr-5.5Mo and 63Co-30Cr-5Mo, $\alpha$-Co and $\varepsilon$-Co phases were identified at matrix and $${\gamma}$-Ni_2$Cr second phase were shown in 63Ni-16Cr. Also, the corrosion resistance of cast structure increased in the order of vacuum pressure casting, high frequency induction casting, and centrifugal casting method.

키워드

참고문헌

  1. B. P. Bannon, E. E. Mild, ASTM STP, 796 (1983) 7
  2. E. P. Lautenschlager, P. Monaghan, Int. Dent. Journal., 43 (1993) 245
  3. K. F. Leinfelder, J. E. Lemons, Philiadelphia, Lea and Febiger. (1988) 139
  4. R. V. Noort, J. Master Sci., 43 (1987) 3801
  5. A. T. Kuhn, Biomaterials, 2 (1981) 68 https://doi.org/10.1016/0142-9612(81)90002-8
  6. D. Brune, G. Hultquist, C. Leygraf, J. Dent. Res., 92 (1984) 262
  7. M. Pourbaix, Biomaterials, 5 (1984) 122 https://doi.org/10.1016/0142-9612(84)90046-2
  8. J. R De Melo, N. R. Gjerdet, E. S. Erichsen, Acta Odontol. Scand., 43 (1985) 69 https://doi.org/10.3109/00016358509046489
  9. E. Angelini, F. Zucchi, J. Mat. Sci., 2 (1991) 27
  10. D, A. PORTER, Van Norstrand Reinhold Co. New York, (1981) 232
  11. 이학열, 금속부식공학, 연경문화사 (1997) P. 104