Development and application of load profiles for thermal qualification testing of receptacle automotive connectors

Abstract

Receptacle contacts often are a weak spot of the reliability in electronic systems. During the application phase of the lifecycle, especially in the automotive wiring harness, connectors experience severe loads such as temperature changes. During qualification testing, accelerated tests simulate these thermal stresses. Yet, only the damage mechanisms relevant for service life must be triggered. However, the increasing complexity of electronic components and wiring harnesses demands a continuous adaptation of test strategies. Therefore, this study develops and applies application-oriented load profiles for thermal qualification testing of connectors. Experiments include load profiles inspired by seasonal changes and daily car usage. The tests are carried out on a relative movement test bench as well as in a thermal cycling testing chamber. Contact resistance progression curves, the surface roughness of the contacts, and the area of the stressed contact zones assist in evaluating the effectiveness of the load profiles. All contacts tested during relative movement experiments show no change in contact resistance. The thermal cycling load profile however results in a significant rise in contact resistance. Additionally, the roughness values show varying damages on the contacts due to the different load profiles.