基于退化模型的失效机理一致性检验方法

有效的加速试验必须保证产品的失效机理不变。针对加速退化试验(ADT)可靠性建模的特点,提出了一种基于退化模型的失效机理一致性检验方法。以基于随机过程和基于退化轨迹拟合的退化模型为例,通过加速系数的2种等效定义分别建立了模型参数与失效机理不变的内在联系,进一步推导出其参数在不同应力下须满足的关系。在合理假定检验样本服从正态分布的基础上,利用t统计量对样本的一致性进行检验。通过2个ADT实例验证了所提检验方法的合理性与可行性。

Test method of failure mechanism consistency based on degradation model

An effective accelerated test must guarantee that the failure mechanism is unchanged. According to the features of reliability modeling under accelerated degradation test (ADT), a test method of failure mechanism consistency based on degradation model is proposed. Taking the degradation models based on stochastic process and degradation path fitting as examples, the inner connection between model parameters and failure mechanism consistency is constructed through two equivalent definitions of acceleration factor. Furthermore, the relationships which should be satisfied at different stresses are deduced. Then t statistic is utilized to test the consistency of samples on the basis that samples are assumed following a normal distribution. Two ADT cases are provided to validate the rationality of the proposed method.