零件动态可靠性建模及早期失效率研究

Time-dependent Reliability Modeling and Study of Early Failure Rate for Component

传统的零件可靠性模型并不能很好地反映随机载荷作用次数对可靠性的影响,同时也掩盖了载荷对零件失效率尤其是早期失效率的贡献。从随机载荷作用的统计学意义出发,运用顺序统计量理论建立了载荷多次作用下的零件可靠性模型;在此基础上,运用泊松随机过程描述载荷的作用过程,建立了零件的动态可靠性模型,并研究了零件可靠度和失效率随时间的变化规律。指出零件的早期失效及失效率并不只是由零件的初始缺陷引起的,而是由随机载荷的作用和零件的强度共同决定的。

The conventional reliability models can’t reflect the effect of times of random loading on the reliability and the contribution of random load to the failure rate, especially, to the early failure rate is covered. In this paper, according to the statistical meaning of random loading, the reliability model is developed with the order statistics theory for the component under repeated loading. Then the loading process is described with Poisson stochastic process, the time-dependent reliability model of component is built and the relationship between reliability and time and that between failure rate and time are studied respectively. It is pointed out that the early failure and failure rate of component isn’t only caused by the initial flaws of component only, but is determined by both random loading and component strength.