A Test Method for Failure Mechanisms Consistency of Accelerated Degradation Test Based on Wiener Process

Accelerated degradation test (ADT) is an important mean to obtain products' degradation data, perform life prediction and assess reliability. An effective ADT needs to ensure failure mechanism consistency of products between various accelerated stresses and normal stress. Thus, a new test method for failure mechanism consistency of accelerated degradation test based on wiener process is proposed in this paper. Frist, degradation modeling for products based on Wiener process is established, and the link between the drift parameter of the Wiener process and accelerated stresses is set up by using accelerated models, such as Arrhenius equation. The relationship among drift parameters under different accelerated stresses is deduced based on the hypothesis that failure mechanism of products under different stresses is consistent when corresponding failure activation energies are invariant. Then, test samples are constructed separately under different stresses and assumed to satisfy a normal distribution, and t statistic is used for these samples to test failure mechanisms consistency. Finally, the accelerated storage degradation data of a certain type of resistor are used as an example to calculate failure mechanism variation interval of this resistor, which verifies the effectiveness of the method proposed in this paper.