Enhancing Connector Lifespan: A Crucial Measure of Reliability

As the demand for flawless performance in electronic products continues to rise, the lifespan of connectors stands out as a crucial indicator for assessing their reliability. In design, enhancing connector lifespan has become a guiding principle. Simultaneously, intensified market competition has driven engineers to seek suitable materials from cost-effective alloys, a primary choice for reducing connector costs. The combined effect of these trends often brings the operational characteristics of copper alloys in connectors closer to their performance limits.

Initial contact force remains a significant factor in connector design and material properties. Elastic deformation transforms into plastic deformation within contacts, resulting in stress release and a subsequent reduction in contact force. If contact force falls below a critical level, functional failure of the contacts can occur. Therefore, predicting stress release as a function of time and temperature becomes a pivotal factor in ensuring connector reliability. In the following paragraphs, SED will delve into stress release testing and its relevance in predicting connector lifespan.

Stress release data serves as an effective tool for design engineers to predict the lifespan of power connectors, enabling informed decisions regarding the selection of contact materials based on existing data. These data have already found widespread application in industries such as computers, communications, and automotive electronics. Currently, lifecycle data for products are notably scarce, particularly in the field of computing. Moreover, this data represents a valuable resource for shortening product development cycles and effective operational periods.

Most connector designers employ stress release data primarily to narrow down the selection of contact materials according to application requirements. However, many designers are also seeking appropriate testing methods for more accurate predictions of connector lifespan characteristics. This approach significantly reduces the required sample quantity for testing and the associated costs.

Presently, automotive connectors within harsh environments and under engine hoods predominantly adopt Level 3 or Level 1 design requirements. The upcoming generation of automotive connectors is expected to operate at higher temperatures. Meanwhile, most non-automotive connectors seem not to require stability under the aforementioned conditions. Nonetheless, high-density connectors necessitate lower initial mating forces, in turn reducing stress release. This underscores the importance of stress release even at lower temperatures.

Determining the standard measurement time for test data relevant to specific applications is generally challenging. Testing times between 1000 hours and 3000 hours at the anticipated operating temperature are suitable for evaluating characteristic data of automotive electronic products. Increasing attention is being paid to characteristic data beyond 3000 hours, extending to 3000-5000 hours (equivalent to a lifespan of 150,000 miles). Extrapolating test data (without considering changes in slope) might lead to an overestimation of contact lifespan, with the degree of overestimation increasing with extended testing periods. The semi-logarithmic graph representation of data at a specific temperature is currently the most widely used method, and it is urgently needed. This approach offers a straightforward means of comparing various materials for a specific application. Nevertheless, it's crucial to thoroughly examine extrapolated data and remain attentive to the possibility of overestimating the ultimate lifespan.