Polymer(Korea) (폴리머)

The Polymer Society of Korea (한국고분자학회)
권호 표지

Effects of Fillers on Fatigue Crack Growth Rate of Ethylene Propylene Diene Monomer

충전제가 EPDM의 피로균열 성장속도에 미치는 영향

  • Hong, Chang-Kook (School of Applied Chemical Engineering, Chonnam National University) ;
  • Jung, Jae-Yeon (School of Applied Chemical Engineering, Chonnam National University) ;
  • Cho, Dong-Lyun (School of Applied Chemical Engineering, Chonnam National University) ;
  • Kaang, Shin-Young (School of Applied Chemical Engineering, Chonnam National University)
  • 홍창국 (전남대학교 응용화학공학부) ;
  • 정재연 (전남대학교 응용화학공학부) ;
  • 조동련 (전남대학교 응용화학공학부) ;
  • 강신영 (전남대학교 응용화학공학부)
  • Published : 2008.05.30
Download PDF
⟨ Previous Next ⟩

Abstract

Crack growth characteristics of elastomeric materials are an important factor determining the strength and durability. In this study, the fatigue crack growth characteristic of filled EPDM compounds with different reinforcing fillers, such as silica and carbon black, was investigated using a newly designed tester. Frequency and test temperature had significant effects on the fatigue crack growth. The crack growth rate decreased with increasing frequency and the rate increased with increasing temperature. A power law relationship between the tearing energy and crack growth was observed for filled EPDM compounds. The crack growth rate reduced with increasing filler contents. Silica filled EPDM showed a better fatigue resistance than carbon black filled EPDM. The crack growth rate of silica filled EPDM decreased up to 30 phr and increased again at 50 phr. The formation of microductile type pits was observed on the fatigue-failure surface of unfilled EPDM, and relatively coarse surface with randomly distributed tear lines was observed on the failure surface of silica filled EPDM.

고무재료의 피로균열 성장특성은 고무제품의 강도와 내구성을 평가하는 매우 중요한 요소이다. 본 연구에서는 자체 제작한 피로균열 성장 측정기를 이용하여 충전제 종류에 따른 EPDM의 피로균열 성장특성을 고찰하였다. 피로균열성장은 진동수와 측정온도에 영향을 받았으며, 진동수가 증가함에 따라 균열성장속도는 감소하였고 온도가 증가함에 따라 균열성장속도는 증가하였다. 충전된 EPDM의 인열에너지와 균열성장속도의 상관관계는 지수법칙을 따랐으며, 충전제의 함량이 증가함에 따라 균열성장속도가 감소하였다. 또한, 실리카로 충전된 EPDM이 카본블랙으로 충전된 EPDM에 비해 더 우수한 피로저항 특성을 보였다. 실리카로 충전된 경우, 균열성장속도는 30 phr까지 감소하다가 그 이후 다시 증가하였다. 미충전 시편의 피로 파괴단면 SEM 사진에서 작고 유연한 파괴자국들이 관찰되었으며, 실리카가 충전된 시편의 단면에서는 보강효과로 인하여 인열 형태가 불규칙 적이고 비교적 거친 표면이 관찰되었다.

Keywords

References

  1. G. J. Lake, Prog. Rubber Technol., 45, 89 (1983)
  2. M. D. Ellul, "Mechanical Fatigue", in Engineering with Rubber: How to Design Rubber Components, A. N. Gent, Editor, Hanser Publishers, New York, 1992
  3. A. A. Griffith, Philos. Trans. R. Soc. Lond., Ser., A221, 163 (1920)
  4. R. S. Rivlin and A. G. Thomas, J. Polym. Sci., 10, 291 (1953) https://doi.org/10.1002/pol.1953.120100303
  5. S. Kaang and C. Nah, Polymer, 39, 2209 (1998) https://doi.org/10.1016/S0032-3861(97)00347-9
  6. G. J. Lake, Rubber Chem. Technol., 68, 435 (1995) https://doi.org/10.5254/1.3538750
  7. A. G. Thomas, Rubber Chem. Technol., 67, G50 (1994) https://doi.org/10.5254/1.3538688
  8. A. I. Kasner and E. A. Meinecke, Rubber Chem. Technol., 69, 92 (1996) https://doi.org/10.5254/1.3538362
  9. G. J. Lake and A. G. Thomas, "Strength", in Engineering with Rubber: How to Design Rubber Components, A. N. Gent, Editor, Hanser Publishers, New York, 1992
  10. N. Rattanasom, T. Saowapark, and C. Deeprasertkul, Polymer Testing, 26, 369 (2007) https://doi.org/10.1016/j.polymertesting.2006.12.003
  11. S. S. Choi, C. Nah, S. G. Lee, and C. W. Joo, Polym. Int., 52, 23 (2003) https://doi.org/10.1002/pi.975
  12. C. K. Hong, H. Kim, C. Ryu, C. Nah, Y. Huh, and S. Kaang, J. Mater. Sci., 42, 8391 (2007) https://doi.org/10.1007/s10853-007-1795-3
  13. M. P. Wagner, Rubber Chem. Technol., 49, 703 (1977)
  14. P. K. Pal and S. K. De, Rubber Chem. Technol., 55, 1370 (1982) https://doi.org/10.5254/1.3535935
  15. Y. Suzuki, M. Owaki, M. Mouri, N. Sato, H. Honda, and K. Nakashima, Toyota Tech. Review, 48, 53 (1998)
  16. S. Kaang, Y. W. Jin, Y. Huh, W. J. Lee, and W. B. Im, Polymer Testing, 25, 347 (2006) https://doi.org/10.1016/j.polymertesting.2005.12.005
  17. P. M. Schubel, E. E. Gdoutos, and I. M. Daniel, Theoretical and Applied Fracture Mechanics, 42, 149 (2004) https://doi.org/10.1016/j.tafmec.2004.08.004
  18. A. I. Medalia and G. Kraus, Reinforcement of Elastomers by Particulate Fillers, Academic Press, San Diego, 1994
  19. R. Rauline (to Michelin), US Patent 5,227,425 (1993)
  20. W. V. Mars and A. Fatemi, Rubber Chem. Technol., 77, 391 (2004) https://doi.org/10.5254/1.3547831
  21. G. J. Lake and P. B. Lindley, J. Appl. Polym. Sci., 8, 455 (1964) https://doi.org/10.1002/app.1964.070080129
  22. E. S. Dizon, A. E. Hicks, and V. E. Chirico, Rubber Chem. Technol., 47, 231 (1974) https://doi.org/10.5254/1.3540429
  23. E. E. Auer, K. W. Doak, and I. J. Schaffner, Rubber Chem. Technol., 31, 185 (1958) https://doi.org/10.5254/1.3542257
  24. K. N. Pandey, D. K. Setua, and G. N. Mathur, Polymer Testing, 22, 353 (2003) https://doi.org/10.1016/S0142-9418(02)00112-5