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Reliability Analysis and Feilure Mechanisms of Coolant Rubber Hose Materials for Automotive Radiator  

Kwak Seung-Bum (Department of Mechanical Design and Production Engineering, Hanyang University)
Choi Nak-Sam (Department of Mechanical Engineering, Hanyang University)
Kang Bong-Sung (Reliability Assessment Center, Korea Research Institute of Chemical Technology)
Shin Sei-Moon (Reliability Assessment Center, Korea Research Institute of Chemical Technology)
Publication Information
Transactions of the Korean Society of Automotive Engineers / v.13, no.5, 2005 , pp. 152-162 More about this Journal
Abstract
Coolant rubber hoses for automobile radiators can be degraded and thus failed due to the influence of contacting stresses of air and coolant liquid under the thermal and mechanical loadings. In this study, test analysis was carried out for evaluating the degradation and failure mechanisms of coolant hose materials. Two kinds of EPDM rubber materials applicable to the hoses were adopted: commonly-used ethylene-propylene diene monomer(EPDM) rubbers and EPDM rubbers with high resistance against electro-chemical degradation (ECD). An increase of surface hardness and a large reduction of failure strain were shown due to the formation of oxidation layer for the specimens which had been kept in a high temperature air chamber. Coolant ageing effects took place only by an amount of pure thermal degradation. The specimens degraded by ECD test showed a swelling behavior and a considerable increase in weight on account of the penetration of coolant liquid into the skin and interior of the rubber specimens. The ECD induced material softening as well as drastic reduction in strength and failure strain. However EPDM rubbers designed for high resistance against ECD revealed a large improvement in reduction of failure strain and weight. This study finally established a procedure for reliability analysis and evaluation of the degradation and failure mechanisms of EPDM rubbers used in coolant hoses for automobile radiators.
Keywords
EPDM rubbers; Thermal oxidative aging; Electro-chemical degradation; Failure mechanisms; Coolant rubber hose;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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