某弹用电子部件贮存寿命评估

目的研究使用定时截尾步进应力加速寿命试验方法评估某弹用电子部件在一定可靠度下的贮存寿命。方法首先将其在应力S_i(i>1)下的作用时间全部转化为在应力S1下的等效作用时间,然后建立威布尔分布加速寿命模型,采用Newton-Raphson方法求解似然方程,得到模型未知参数的极大似然估计结果,最后外推得到正常温度下的贮存寿命。结果在25℃下可靠度为0.9999时,使用定时截尾步进应力加速寿命试验方法评估电子部件的寿命约为11.89年,使用恒定应力加速寿命试验评估寿命为13.32年,两种试验方法的评估结果相差不大。结论步进应力加速寿命试验时间短、样本量少、成本低,相对于恒定应力加速寿命试验方法,具有一定的优越性。

The Storage Life Assessment of Electronic Components in a Missile

Objective To study estimating the storage life of electronic components in a Missile under a certain degree of reliability based on censoring data from step-up-stress accelerated life test.Methods First, the testing time under the stress of Si (i>1) was converted to the equivalent time under the stress S1. Then, a step-up-stress accelerated life test model based on Two-parameter Weibull distribution was established and the unknown parameter was solved by Newton-Raphson method. At last, The storage life under normal stress was estimated by Arrhenius equation.Results when the reliability was 0.9999 at 25 degrees Celsius, the storage life of electronic components based on censoring data from step-up-stress accelerated test was about 11.89 years, and the life based on constant-stress accelerated test was about 13.32 years, the evaluation results of the two test methods were not quite different.Conclusion step-up-stress accelerated life test time was short, the sample was small and the cost was low, has certain superiority compared with constant-stress accelerated test.