Abstract:

Hermetically sealed electromagnetic relay (HSER) used in aviation and aerospace have high requirements for long-term on-load reliability.Accelerated degradation test is usually used to predict reliable life.In the multi-stress accelerated degradation test, the failure mechanism of HSER must be consistent, otherwise the product life prediction will have a large deviation.Therefore, the study on the failure mechanism consistency of accelerated degradation test is of great significance to improve the accuracy of reliable life prediction of HSER. Firstly, based on the principle of likelihood ratio detection, a consistency criterion is proposed to design an accelerated degradation test for a typical HSER.The test data is analyzed, and the consistency is checked by the criterion.After obtaining a consistency conclusion, the destructive physical experiments are carried out to analyze the degradation of the permanent magnet and spring.The effectiveness of the proposed criterion is verified.

Key words: hermetically sealed electromagnetic relay (HSER), failure mechanism consistency, likelihood-ratio test, destructive physical analysis (DPA)