三参数Weibull分布竞争失效场合变应力加速寿命试验统计分析

Statistical Inference of Varying-stress Accelerated Life Test with Competing Failures Based on Three-parameter Weibull Distribution

三参数Weibull分布(Three-parameter Weibull distribution,TPWD)作为一种应用广泛的分布形式,具有很强的数据拟合能力且对于描述具有渐变性失效特征的失效模式如磨损、疲劳、腐蚀、老化等的的寿命分布具有更加明确的物理意义。针对产品失效模式为TPWD的竞争失效场合加速寿命试验统计分析的需求,根据TPWD的特点,在竞争失效加速寿命试验统计分析基本模型的基础上系统研究TPWD竞争失效变应力加速寿命试验统计分析方法,建立参数估计的极大似然模型并进行实例验证。实例结果表明,建立的TPWD竞争失效变应力加速寿命试验统计分析方法和模型是正确可行的,具有很好的估计效果。

Three-parameter Weibull distribution （TPWD） is widely used in reliability analysis for products. It has a very good capability for data fitting and more unambiguous physical meaning for life evaluation to describe the life distribution of products that have the characteristics of progressive failure such as wear, fatigue, corrosion and aging failure. To meet the demand of statistical inference of accelerated life test （ALT） with competing failures when all the failure modes are three-parameter Weibull distribution, the statistical inference method of ALT with three-parameter Weibull distribution competing failures is studied based on the properties of TPWD and basic models of ALT. The maximum likelihood estimation model for parameters estimation is also built. Result of simulation example proves that the statistical inference method and model proposed is correct and has very good effect.