考虑强度退化的零件及系统可靠性分析  

Reliability Analysis of Components and System Considering Degradation of Strength

作　　者：高鹏[1] 谢里阳[1] 

机构地区：[1]东北大学机械工程与自动化学院,沈阳110819

出　　处：《机械工程学报》2010年第24期162-167,共6页Journal of Mechanical Engineering

基　　金：国家自然科学基金(50775030);国家重点基础研究发展计划(973计划;2006CB605005)资助项目

摘　　要：指出传统载荷—强度干涉模型适用于载荷作用一次或者静态的零件可靠度计算。零件的强度是随机载荷大小和作用次数的函数,所以假设载荷和强度相互独立的干涉模型无法用于计算考虑强度退化时零件及系统的可靠度。通过随机载荷的统计特性建立强度与随机载荷的关系。当载荷历程为泊松过程时,分析零件的可靠性和失效率与时间的关系,并建立考虑共因失效时串联系统和并联系统的可靠性模型。研究表明,零件初始强度的分散性对零件的可靠度和失效率有很大影响,载荷的相关性使并联系统的可靠度降低,使串联系统的可靠度升高。The traditional loading-strength interference model is suitable for reliability calculation when random loading acts once or the static reliability calculation.The strength of a component is the function of magnitude and frequency of loading.The traditional loading-strength interference model cannot be used to calculate the reliability of components and system when considering strength degradation,because it assumes that loading and strength are mutually independent.The relationship between loading and strength is established through the statistic characteristics of random loading.When the loading process is Poisson process,the relationship between reliability and time and the relationship between failure rate and time are analyzed.Then the reliability models of series system and parallel system are derived.The study case shows that dispersity of original strength has an influence on reliability and failure rate of components and that relativity of loading makes the reliability of a parallel system decrease while relativity of loading makes the reliability of a series system increase.

关 键 词：载荷 强度 可靠度 失效率 二维分布 

分 类 号：TH122[机械工程—机械设计及理论] TB114.3[理学—概率论与数理统计]