基于加速因子的Wiener退化产品可靠性评估方法

Reliability Assessment Approach for Wiener-type Degradation Based on Acceleration Factor

在加速退化试验中,难以准确确定参数和应力的关系,针对目前过于依赖主观经验来确定参数与应力的关系,提出了基于加速因子的Wiener退化产品的可靠性评估方法。首先,根据加速因子应当是一个只与应力有关的常数,推导得到了Wiener过程漂移参数和扩散参数的约束关系。然后依据Arrhenius模型推导得到漂移参数和扩散参数的加速模型。最后以某引信用O型橡胶密封圈为例,研究了变温度情况下应用加速因子推算贮存可靠性的方法,结果表明此种情况下产品平均贮存寿命约12.7~13.3年。

It is difficult to exactly figure out the changing rules of parameters with stress in the accelerated degradation test. With regard to the defect of subjective judgements,a new reliability assessment method for Wiener-type degradation based on acceleration factor is presented. Firstly,the acceleration factor between any two different stress levels should be a constant,so the special rules between the drift parameter and diffusion parameter are derived. Then,the accelerated models of drift parameter and diffusion parameter are also given according to Arrhenius model. Finally,a case involving the O-type rubber sealing for a fuse is used to illustrate the application. The method of calculating the reliability of the product in changing temperatures is also given. The result shows that the storage life in the given changing temperatures is between 12. 7 and 13. 3 years.