多应力小样本加速寿命试验设计与评估方法  

Design and Evaluation Method for Multi-Stress Accelerated Life Test with Small Samples

作　　者：傅惠民[1] 郭建超 付越帅 李子昂 FU Hui-min;GUO Jian-chao;FU Yue-shuai;LI Zi-ang(Research Center of Small Sample Technology,Beihang University,Beijing100191,China)

机构地区：[1]北京航空航天大学小样本技术研究中心,北京100191

出　　处：《机电产品开发与创新》2024年第3期1-4,共4页Development & Innovation of Machinery & Electrical Products

基　　金：国家自然科学基金(U2037602)《月基装备自主操控与多机协同基础理论与关键技术研究》。

摘　　要：针对目前多应力加速寿命试验需要的组合应力水平多、时间长、费用高的问题,提出一种多应力小样本加速寿命试验设计与评估方法。该方法建立了正常使用应力水平下可靠寿命的单侧置信下限与加速应力水平下的可靠寿命置信限之间的数学关系式,给出了正常使用应力水平下高置信度、高可靠度的可靠寿命单侧置信下限计算公式。文中首先针对工程上最常用的双应力情况,分别建立了无耦合和有耦合的双应力小样本加速寿命试验设计与评估方法,它只需在三个(无耦合)或四个(有耦合)组合应力水平下进行加速寿命试验,即可对产品在正常使用应力水平下高置信度、高可靠度的可靠寿命进行评估。然后针对一般的m种应力情况,建立了基于多应力线性加速模型的小样本加速寿命试验设计与评估方法,它只需在m+1个组合应力水平下进行加速寿命试验,即可求得产品在正常使用应力水平下高置信度、高可靠度的可靠寿命单侧置信下限。该方法计算简单,而且对完全数据、不完全数据以及各种分布均适用。大量工程算例和Monte Carlo模拟验证表明,与传统多应力加速寿命试验方法相比,本文方法不但可以节省大量试样和试验时间,而且理论上更加严谨,精度更高。A small-sample multi-stress accelerated life test design and evaluation method is proposed to solve the problems of conventional multi-stress accelerated life tests,such as many combined stress levels,long period,high cost.By establishing the relationship between the one-sided lower confidence limit of reliable life at normal stress level and the confidence limits of reliable life at accelerated stress levels,the one-sided lower confidence limit of reliable life at normal stress level can be assessed with high confidence and high reliability.Firstly,for the most commonly used dual-stress situation,the design and evaluation methods for small-sample dual-stress accelerated life test without and with coupling are established,respectively.Using these methods,only three(without coupling)or four(with coupling)combined stress levels need to be selected in the life tests,and the reliable life at normal stress level of the product can be evaluated with high confidence and high reliability.Then,for the general m-stress situation,a small-sample multi-stress accelerated life test design and evaluation method is proposed based on the multi-stress linear acceleration model,which requires conducting accelerated life tests at m+1 combined stress levels,and the one-sided lower confidence limit of reliable life at the normal stress level can be obtained.The method is easy to implement and applicable to complete data,incomplete data and various lifetime distributions.Numerous case studies and Monte Carlo simulations show that the proposed method not only saves the specimens and test time,but also is more theoretically rigorous and more accurate than the conventional methods.

关 键 词：多应力 加速寿命试验 小样本 试验设计 可靠寿命 置信限 

分 类 号：TB114.3[理学—概率论与数理统计]