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테이프 캐스팅 산화물 층상 복합체에서의 균열

Cracks in Tape Cast Oxide Laminar Composites

  • Kim, Ji-Hyun (School of Materials Science and Engineering, Pusan National University) ;
  • Yang, Tae-Young (School of Materials Science and Engineering, Pusan National University) ;
  • Lee, Yoon-Bok (School of Materials Science and Engineering, Pusan National University) ;
  • Yoon, Seog-Young (School of Materials Science and Engineering, Pusan National University) ;
  • Park, Hong-Chae (School of Materials Science and Engineering, Pusan National University)
  • 발행 : 2002.01.01

초록

테이프 캐스팅된 알루미나/지르코니아 또는 뮬라이트/지르코니아를 표면층으로 알루미나/지르콘(소결시 반응결합 뮬라이트/지르코니아 유도)을 내부층으로 적층하고 고온가압소결함으로써 층상 복합체를 제조하였다. 소결체에서 다양한 형태의 균열을 관찰 할 수 있었으며, 이는 주로 표면층으로의 횡단균열(channel crack, 계면에 수직방향으로 전파되는 균열), 중간층 내에서의 종단균열(transverse crack, 계면에 거의 평행한 방향으로 전파되는 균열)과 증간사이를 분리시키는 계면균열(interface crack, 계면을 따라 전파되는 균열)들로 구성되어 있었다. 이러한 균열들은 층을 이루는 복합산화물간의 열팽창계수의 차이에 의해 형성된 것으로 여겨졌다. 특히, 표면층을 뮬라이트/지르코니아로 적층하였을 경우 층간 계면에 평행한 균열과 중간층 내로의 종단균열이 생성되었으나, 알루미나/지르코니아로 하였을 경우는 이러한 균열이 확인되지 않았다. 한편, 압흔하중에 의한 적층체의 잔류응력 역시 표면층의 종류에 따라서 상이한 양상을 나타내었다.

Hot-pressure sintered laminar composites with alumina/zirconia or mullite/zirconia as an outer layer and alumina/zircon (resulting in reaction-bonded mullite/zirconia during sintering) as an inner layer were fabricated by tape casting and lamination. Various forms of crack were observed in sintered laminar composites, these cracks included channel cracks in the outer layer, transverse cracks in the inner layer and interface cracks debonding interlayer. Based on detailed microscopic observations, the cracks were attributed to thermal expansion mismatch between the oxides consisting of the each layer. In particular, the interlayer and transverse cracks were confirmed in the laminates consisted of the mullite/zirconia system as the outer layers, however, those cracks were not observed in the alumina/zirconia system used. In addition, the crack propagation did not exhibit same behavior in the two kinds of outer layer when the indentation load was applied.

키워드

참고문헌

  1. A. Selcuk and A. Atkinson, 'Strength and Toughness of Tape-cast Yttria-stabilized Zirconia,' J. Am. Ceram. Soc., 83 [8] 2029-35 (2000) https://doi.org/10.1111/j.1151-2916.2000.tb01507.x
  2. D. B. Marshall, J. J. Ratto and F. F. Lange, 'Enhanced Frac-ture Toughness in Layered Microcomposites of $Ce-ZrO_2$ and $Al_2O_3$,' J. Am. Ceram. Soc., 74 [12] 2979-87 (1991) https://doi.org/10.1111/j.1151-2916.1991.tb04290.x
  3. J. R. Mawdsley, D. Kovar and J. W. Halloran, 'Fracture Behavior of Alumina/Monazite Multilayer Laminates,' J. Am Ceram. Soc., 83 [4] 802-08 (2000) https://doi.org/10.1111/j.1151-2916.2000.tb01278.x
  4. H. J. Jung, E. S. Na and S. C. Choi, 'The Fabrication and Electrical Properties of PMS-PZT Ceramics Using a Tape Casting Method(in Kor.),' J. Kor. Ceram. Soc., 38 [9] 860-65 (2001)
  5. B. K. Jang and S. K. Woo, 'Toughening of $Al_2O_3/LaAl_{11}O_{18}$Composites(in Kor.),' J. Kor. Ceram. Soc., 35 [12] 1266-73 (1998)
  6. M. L. Santella, 'A Review of Techniques for Joining Advanced Ceramics,' Am. Ceram. Bull., 71 [6] 947-54 (1992)
  7. P. Z. Cai, D. J. Green and G. L. Messing, 'Constrained Den-sification of Alumina/Zirconia Hybrid Laminates, I: Exper-imental Observations of Processing Defects,' J. Am. Ceram. Soc., 80 [8] 1921-39 (1997)
  8. P. Z. Cai, D. J. Green and G. L. Messing, 'Constrained Den-sification of Alumina/Zirconia Hybrid Laminates, II: Vis-coelastic Stress Computation,' J. Am. Ceram. Soc., 80 [8] 1940-48 (1997) https://doi.org/10.1111/j.1151-2916.1997.tb03076.x
  9. M. Oechsner, C. Hillman and F. F. Lange, 'Crack Bifur-cation in Laminar Ceramic Composites,' J. Am. Ceram. Soc., 79 [7] 1834-38 (1996) https://doi.org/10.1111/j.1151-2916.1996.tb08003.x
  10. R. Watanabe, 'Powder Processing of Functionally Gradient Materials,' MRS Bull., 20 32-4 (1995)
  11. Y. G. Jung, 'Sintering of Layer Structure Materials: Effect of Starting Material on Sintering Defects and Residual Stress(in Kor.),' J. Kor. Ceram. Soc., 36 [1] 61-8 (1999)
  12. M. Niino and T. Kawai, 'Concept of Functionaly Gradient Materials,' Electronic Mat., 8 103-08 (1991)
  13. S. Ho and Z. Suo, 'Tunneling Cracks in Constrained Lay-ers,' J. Appl. Mech., 60 [12] 890-94 (1993) https://doi.org/10.1115/1.2900998
  14. J. She, S. Scheppokat, R. Janssen and N. Claussen, 'Reac-tion-bonded Three-layer Alumina-based Composites with Improved Damage Resistance,' J. Am. Ceram. Soc., 81 [5] 1374-76 (1998) https://doi.org/10.1111/j.1151-2916.1998.tb02495.x
  15. J. S. Wallace, G. Petzow and N. Claussen, 'Microstructure and Property Development in Situ-reacted $Mullite-ZrO_2$Composites,' pp. 436-42 in Advanced in Ceramics, Vol. 12, Science and Technology of Zirconia. Ed. by N. Claussen, M. Ruhle and A. H. Heuer. American Ceramic Society, West-erville, OH, 1984