Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Electrochemical Combined-Stress Degradation Test and Failure Mechanisms of EPDM Rubber for Automotive Radiator Hoses

자동차 냉각기 호스용 EPDM 고무의 전기화학적 복합노화시험 및 고장메커니즘

  • Kwak, Seung Bum (Dept. of Mechanical Engineering, Hanyang Univ.) ;
  • Choi, Nak Sam (Dept. of Mechanical Engineering, Hanyang Univ.) ;
  • Shin, Sei Moon (Reliability Assessment Center, Korea Research Institute of Chemical Technology)
  • 곽승범 (한양대학교 기계공학과) ;
  • 최낙삼 (한양대학교 기계공학과) ;
  • 신세문 (한국화학연구원 신뢰성평가센터)
  • Received : 2011.10.11
  • Accepted : 2012.10.10
  • Published : 2013.01.01
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Abstract

Coolant rubber hoses for automotive radiators can degrade under thermal and mechanical loadings and thus fail owing to the influences of locally formed electricity. In this study, an advanced test method was developed to simulate the failure of a rubber hose. The aging behavior of carbon-black-filled ethylene-propylene diene monomer (EPDM) rubber used as a radiator hose material under a combination of electrochemical stresses and tensile strain was analyzed. The changing behaviors of the current and the resistance as a function of the aging time were analyzed in consideration of the tensile strain, voltage, and aging temperature. Sectioned specimens clarified the failure mechanisms of the aged skin layer under the combined electrochemical stresses.

자동차용 냉각기 고무호스는 열과 기계적 하중을 받으면서 국부적으로 형성된 전기적 영향으로 인해 노화와 고장이 발생한다. 본 연구에서는 개선된 시험방법을 이용하여 고무호스의 파괴거동을 재현하였다. 냉각기 고무호스 재료인 카본블랙이 함유된 EPDM 고무를 사용하여 인장응력과 전기화학적 복합 스트레스를 가하여 노화거동을 분석하였다. 노화 시간에 따른 전류 및 저항의 변화거동을 관찰하였으며 인장 변형 스트레스와 전압 및 노화온도 조건에 따른 노화거동을 분석하였다. 고무 시험편을 수직면으로 정밀하게 절단하여 시험편 표면 및 내부의 변화거동을 분석하여 전기화학적 노화거동과 고장메커니즘을 규명하였다.

Keywords

References

  1. 2001, "Coolant Hose for Automotive Radiator Guide Book RS M0004," Korean Agency for Technology and Standards.
  2. 2001, "Coolant Hose for Automotive Radiator Reliability Standards RS M0004," Korean Agency for Technology and Standards.
  3. 2000, Test Methods for Evaluating the Electrochemical Tesistance of Coolant System Hoses and Materials, SAE J1684.
  4. Vroomen, G. and Verhoef, H., 1994, "Electrochemical Degradation of EPDM Cooling Water Hoses," KGK Kautschuk Gummi Kunststoffe, Vol. 48, pp. 749-753.
  5. Vroomen, G. L. M., Lievens, S. S. and Maes, J. P., 1999, "Influence of Engine Coolant Composition on the Electrochemical Degradation Behavior of EPDM Radiator Hoses," Engine Coolant Testing: Fourth Volume, ASTM　STP 1335，pp. 183-195.
  6. Kwak, S. B., Choi, N. S., Kang, B. S. and Shin, S. M., 2005, "Reliability Analysis and Failure Mechanisms of Coolant Rubber Hose Materials for Automotive Radiator," Transactions of KSAE, Vol. 13, No. 5, pp. 152-162.
  7. Kwak, S. B., Choi, N. S., Choi, Y. J. and Shin, S. M., 2005, "Nondestructive Characterization of Degradation of EPDM Rubber for Automotive Radiator Hoses," Journal of the Korean Society for Nondestructive Testing, Vol. 25, No. 5, pp. 368-376.
  8. Kwak, S. B., Choi, N. S., Shin, S. M. and Shin, W. G., 2007, "Degradation Behavior and Micro-hardness Analysis of a Coolant Rubber Hose for Automotive Radiator," Trans. Korean Soc. Mech. Eng. A, Vol. 31, No. 9, pp. 915-923. https://doi.org/10.3795/KSME-A.2007.31.9.915
  9. Kwak, S. B., Choi, N. S. and Kim, J. K., 2009, "Cross-link Density Measurement and Thermal Oxidative Degradation Analysis of a Carbon Black Compounded EPDM Rubber Hose," Journal of the Korean Society for Composite Materials, Vol. 22, No. 3, pp. 35-43.
  10. Kwak, S. B., Seo, B. S. and Choi, N. S., 2011, "An Electro-chemical Combined-stress Degradation Test of Rubber for Automotive Radiator Hoses," Transactions of KSAE, Vol. 19, No. 4, pp. 107-113.
  11. Maurizio Lucchi, 2000, "New CABOT Carbon Blacks for Improved Electro-chemical Degradation Resistance," IRC 2000 Rubber Conference.

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  1. Mechanical property behavior and aging mechanism of carbon-black-filled EPDM rubber reinforced by carbon nano-tubes subjected to electro-chemical and thermal degradation vol.31, pp.9, 2017, https://doi.org/10.1007/s12206-017-0802-0
  2. Electrochemical degradation tests on a carbon-black-filled ethylene propylene diene monomer rubber under tensile strain pp.2041-2991, 2017, https://doi.org/10.1177/0954407017694412
  3. Accelerated Life Prediction of Ethylene-Propylene Diene Monomer Rubber Subjected to Combined Degradation vol.38, pp.5, 2014, https://doi.org/10.3795/KSME-A.2014.38.5.505