Abstract Considering the complex product working circumstances under severe conditions, this paper first specifies the shock processes that a product experiences. The multi-stage description of competing failure processes is accomplished by considering various factors affecting the performance degradation process as well as by introducing the soft failure threshold in order to effectively illustrate the overall failure process of the product. The concepts of shock damage and intensive shocks are introduced to modify the traditional shock models. The difficult problem of adding the arrival time of shocks to the reliability model is solved by using the multivariable integrals. The competing failure model based on the extreme shock damage and the delta-shock competing failure model considering the intensive shocks are presented. Finally, the proposed models are applied to evaluate the reliability of a certain micro engine. The influence of the parameters on the model reliability is analyzed, and the proposed models are compared with an existing reliability model. The results demonstrate that the proposed models can effectively describe the competing failure process and show certain feasibility and theoretical reference values.

中文翻译：

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产品严酷工况下失效阈值不断变化的竞争失效过程的可靠性建模

摘要 针对产品在恶劣条件下的复杂工作环境，本文首先详细说明了产品所经历的冲击过程。竞争失效过程的多阶段描述是通过考虑影响性能退化过程的各种因素以及引入软失效阈值来完成的，以有效地说明产品的整体失效过程。引入冲击损伤和密集冲击的概念来修改传统的冲击模型。利用多变量积分解决了在可靠性模型中加入冲击到达时间的难题。提出了基于极端冲击损伤的竞争失效模型和考虑强烈冲击的delta-shock竞争失效模型。最后，所提出的模型被应用于评估某个微型发动机的可靠性。分析了参数对模型可靠性的影响，并将提出的模型与现有的可靠性模型进行了比较。结果表明，所提出的模型能够有效地描述竞争失效过程，具有一定的可行性和理论参考价值。