Degradation and life prediction of a natural rubber engine mount compound

摘要

To assess and predict the functional life of a natural rubber engine mount compound, the mechanical property changes were determined under accelerated aging conditions. The rubber was aged at temperatures ranging from 70 to 110 degrees C for times ranging from 1 h to 5 weeks. Tensile and fatigue measurements were used to characterize the aging trends and mechanisms of the engine Mount compound. With the time-temperature superposition approach, the activation energy was found to be about 98 kJ/mol for the elongation at break, 93 kJ/mol for the tensile strength, and 60 kJ/mol for the fatigue life. The tensile strength after aging for 13 weeks at 50 degrees C was predicted to be 18.73 MPa, which was very close to the experimental value of 19.04 +/- 2.25 MPa. With a 50% reduction in the tensile strength used as the failure criterion, it was predicted that the tensile strength of the engine mount compound would take 80 days to decrease by 50%, at 70 degrees C. At 23 degrees C, it would last approximately 140 times (31 years) its lifetime at 70 degrees C. (C) 2008 Wiley Periodicals, Inc.