This article describes how a step‐stress accelerated life test (SSALT) can be designed for testing the fatigue life and reliability of structural components with a dominant failure mode. With simple numerical simulations of the crack's propagation in the notched area of the structural part for different loading levels, the slope of the S–N curve for a structural component is initially estimated. Then, a very few fatigue–life experiments are carried out in the high‐cycle domain to determine the intercept of the structure's S–N curve. By considering the scatter from the material's P–S–N curve, different SSALT designs for the structural component can be composed and checked for their expected acceleration factor. The procedure is experimentally validated for the case of a notched specimen and two different SSALT designs. From the results it can be concluded that the predicted durations of the SSALT experiments correlate well with the real experiments.

中文翻译：

---

基于有限元方法的步态应力加速寿命试验设计，用于评估结构部件的疲劳可靠性

本文介绍了如何设计步进应力加速寿命测试（SSALT），以测试具有主要失效模式的结构部件的疲劳寿命和可靠性。通过简单的数值模拟，研究了在不同载荷水平下裂纹在结构零件的缺口区域中的传播，初步估算了结构部件的S–N曲线的斜率。然后，在高循环域中进行了很少的疲劳寿命试验，以确定结构的S–N曲线的截距。通过考虑材料的P–S–N曲线的散布，可以组成结构部件的不同SSALT设计并检查其预期的加速因子。该程序已针对带有缺口的标本和两种不同的SSALT设计进行了实验验证。