Contact stress relaxation and resistance change relationships inaccelerated heat age testing

摘要

This paper reviews the development of the present practice of heatage reliability testing, (temperature life testing), and formallyidentifies and addresses the inherent concerns of this procedure. A 302day heat age test has been completed to evaluate the resistance behaviorof two D-subminiature contacts at three different elevated temperatures.The results indicate that in heat age conditioning, resistance isaffected by mechanisms other than normal force degradation. Furthermore,the effect reduction in normal force has on a contact may not be evidentunless the contact is disturbed. Therefore, changes in resistance as aresult of heat aging are not necessarily indicative of changes that mayoccur due to loss of normal force in actual use. This investigationsuggests that accelerated heat age testing should be primarily used as apreconditioning test prior to exposing contacts to other environmentswhere reduced normal force may make contacts more susceptible to otherfailure mechanisms