摘要
为解决传统单个恒定应力加速试验条件下,寿命评估周期长、成本高的问题,基于气缸失效机理,建立气缸寿命-应力模型,在假定气缸产品寿命服从两参数威布尔(Weibull)分布的条件下,以极大似然估计(MLE)渐近方差最小为设计原则,选取温度和频率作为试验应力,建立气缸双应力交叉步降试验优化模型。通过对试验数据的分析、优化理论和传统理论的外推精度和试验效率的比较,证明了优化模型和交叉步降加速寿命试验方法在气缸寿命评估中的可行性,以及加速模型的正确性。
According to the required standards in the mechanical industry as well as the current methods of constant stress accelerated life testing, it will cost many resources to complete the life test.Thus, it needs a new and more effective method to fulfil the pneumatic cylinder life tests. The life-stress model for cylinder based on the failure mechanism is built as well as dual-crossed step-down-stress ALT model, with the least MLE asymptotic variance as a design objective, and with the assumption that the service life of product obeys a 2-parameter Weibull distribution. For the test, the temperature and frequency are chosen as test stresses, and the test platform, as well as the test gas-source circuit and automatic control system are designed. Double-stress ALTs under optimal plans will be compared with the traditional ones, meanwhile, the feasibility and correctness of the new plans will be proved, through analysis based on the experimental data and comparison between extrapolation accuracy and test efficiency.
作者
王德义
陈娟
Wang Deyi;Chen Juan(Beijing Aerospace Automatic Control Institute,Beijing 100854,China;School of Mechanical Engineering and Automation,Beijing 100854,China)
出处
《质量与可靠性》
2019年第4期35-39,45,共6页
Quality and Reliability
关键词
加速寿命试验
双应力交叉步阶
威布尔分布
寿命-应力模型
气缸
accelerated life testing(ALT)
double-crossed-step-stress(DCSS)
Weibull distribution
life-stress relationship
pneumatic cylinder
