산화억제제 첨가에 으한 탄소/탄소 복합재료의 물성에 관한 연구: 3. 탄소/탄소 복합재료의 열안정성에 대한 이규화 몰리브덴의 효과

박수진; 조민석; 이재락

Polymer(Korea), Vol.23, No.2, 305-311, March, 1999

Influence of Oxidation Inhibitor on Carbon-Carbon Composites: 3. Effect of Molybdenum Disilicide on Thermal Stability of the Composites

박수진, 조민석, 이재락

초록

탄화 매트릭스의 전구체로 사용된 페놀수지에 세라믹 분말인 이규화 몰리브덴 (MoSi₂)을 0, 4, 12, 20%의 중량비로 각각 고르게 분산시켜, 이를 단일 공정으로 탄화 (1100 ℃) 및 흑연화 (2200 ℃)시켜서 일방향 탄소/탄소 복합재료를 제조하였다. 본 연구에서는 산화억제성 및 고온에서 취성-연성 전이 특성을 지닌 MoSi₂가 복합재료에 미치는 영향을 대기중에서 열중량분석기 (TGA)를 사용하여 조사하였다. 또한, TGA 분석 결과를 적분에 의한 열분해 진행온도 (IPDT)와 열분해시의 활성화 에너지를 이용하여 열안정성에 대하여 살펴보았다. 결과적으로, Doyle에 의해 정리된 IPDT와 Horowitz-Metzger에 의한 적분법으로부터 얻은 활성화 에너지로부터 살펴본 열안정성은 탄소/탄소 복합재료에 열처리온도가 증가함에 따라, MoSi₂의 첨가량이 증가함에 따라 향상됨을 알 수 있었다. 이것은 고온에서 발현되는 BDT에 의하여 섬유-수지-MoSi₂의 계면간의 물리적 결합력의 증가로 인한 결과로 사료된다.

PAN-based carbon fibers, impregnated with phenolic resin used as a precursor of carbonized martix, was modified by the addition of molybdenum disilicide(MoSi₂)in different concentrations. i.e., 0, 4, 12 and 20% by weight. Thus, the unidirectional carbon fiber-reinforced phenplic matrix composites were manufactured by prepreg method, and were submitted to carbonization (heat treated to 1100 ℃) and graphitization (to 2300 ℃). The influence of MoSi₂ concentrations having oxidation inhibition and brittle-to-ductile transition (BDT) properties at high temperatures on the thermal stability of the composites was investigated by ites were characterized by the intergral procedural decomposition temperature (IPDT) obtained method of Horowitz-Metzger. It was found that the thermal stabilities increased with increasing the final heat treatment temperature (HTT)and the concentration of MoSi₂ in C/C composites. This seems to be a consequence of the improvement in physical adhesion between fiber-Matrix-MoSi₂ of the composites, due to the BDT at high temperatures.

Keywords:carbon/carbon composites;MoSi2;thermal stability;activation energy

[References]

Gee SM, Little JA, J. Mater. Sci., 26, 1093 (1991)
Mckee DW, Carbon, 24, 551 (1987)
Park SJ, Lee JR, J. Mater. Sci., 33(3), 647 (1998)
Fitzer E, Carbon, 25, 163 (1988)
Savage G, "Carbon-Carbon Composites," chap. 6, Chapman & Hall, London (1993)
Park SJ, Park BJ, J. Mater. Sci. Lett., in press
Banks M, Ebdon JR, Johnson M, Polymer, 34, 4547 (1993)
Cho D, Lee JY, Yoon BI, Polym.(Korea), 17(5), 521 (1993)
Ragan S, Emmerson GT, Carbon, 30, 339 (1992)
Choudhary V, Fitzer E, Heine M, Angew. Makromol. Chem., 160, 17 (1988)
Doyle CD, Anal. Chem., 33, 77 (1961)
Horowitz HH, Metzger G, Anal. Chem., 35, 1464 (1963)
Jandhyala S, J. Am. Ceram. Soc., 76, 226 (1993)
Zhang BR, Marino F, J. Am. Ceram. Soc., 80, 269 (1996)
Park SJ, Cho MS, Lee JR, Polym.(Korea), 22(6), 972 (1998)
Cho MS, Park SJ, Lee JR, Pak PK, Polym.(Korea), 22(6), 987 (1998)
Lee EW, Cook J, Khan A, Mahapatra R, Waldman J, Jom., 43, 54 (1991)

[Referenced By]

[1] Gee SM, Little JA, J. Mater. Sci., 26, 1093 (1991)

[2] Mckee DW, Carbon, 24, 551 (1987)

[3] Park SJ, Lee JR, J. Mater. Sci., 33(3), 647 (1998)

[4] Fitzer E, Carbon, 25, 163 (1988)

[5] Savage G, "Carbon-Carbon Composites," chap. 6, Chapman & Hall, London (1993)

[6] Park SJ, Park BJ, J. Mater. Sci. Lett., in press

[7] Banks M, Ebdon JR, Johnson M, Polymer, 34, 4547 (1993)

[8] Cho D, Lee JY, Yoon BI, Polym.(Korea), 17(5), 521 (1993)

[9] Ragan S, Emmerson GT, Carbon, 30, 339 (1992)

[10] Choudhary V, Fitzer E, Heine M, Angew. Makromol. Chem., 160, 17 (1988)

[11] Doyle CD, Anal. Chem., 33, 77 (1961)

[12] Horowitz HH, Metzger G, Anal. Chem., 35, 1464 (1963)

[13] Jandhyala S, J. Am. Ceram. Soc., 76, 226 (1993)

[14] Zhang BR, Marino F, J. Am. Ceram. Soc., 80, 269 (1996)

[15] Park SJ, Cho MS, Lee JR, Polym.(Korea), 22(6), 972 (1998)

[16] Cho MS, Park SJ, Lee JR, Pak PK, Polym.(Korea), 22(6), 987 (1998)

[17] Lee EW, Cook J, Khan A, Mahapatra R, Waldman J, Jom., 43, 54 (1991)