Effects of Thermal Aging on Properties and Life-time Prediction of NBR and EPDM Vulcanizates

열 노화에 따른 NBR과 EPDM 가황물의 물성변화 및 노화수명 예측

  • Woo, C.S. (Micro Applied Mechanics Lab., Korea Institute of Machinery & Materials) ;
  • Choi, S.S. (Dept. of Applied Chemistry, Sejong University)
  • 우창수 (한국기계연구원 마이크로응용역학연구실) ;
  • 최성신 (세종대학교 응용화학과)
  • Published : 2005.06.30

Abstract

Material characteristics and lifetime evaluation are very important in design procedure to assure the safety and reliability of the rubber components. In this paper, the material test and accelerated heat aging test were carried out to predict the useful life of NBR and EPDM rubber mount for a compression motor which is used in a refrigerator. In order to investigate the effects of heat-aging on the material properties, crosslink density, modulus at 100% strain, stress-strain curves were obtained from uniaxial and equi-biaxial tensile tests. The change of compression set were used for assessment of the useful life and the time to threshold value were plotted against the reciprocal of absolute temperature to give the Arrhenius plot. The useful life at variable temperatures are obtained in the Arrhenius relationship.

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