A new fatigue testing technique, the small bulge fatigue (SBF) test using a small disk‐type specimen with flat and concave surfaces, was developed in this study. In the technique, a cyclic oil pressure could be alternatively applied to both specimen surfaces at the frequency of 10 Hz. After some verification tests for the displacement and strain measurements, type 316 austenitic stainless steel specimens were subjected to a preliminary test using this newly developed testing technique. As a result, the SBF test results (S‐N curve) were in good agreement with those of conventional fatigue tests by defining fatigue life as the number of cycles to the sudden drop in oil pressure because of fracture.

中文翻译：

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利用小圆盘形试样开发小凸起疲劳测试技术

在这项研究中，开发了一种新的疲劳测试技术，即使用具有平坦表面和凹形表面的小型圆盘形试样进行的小凸起疲劳（SBF）测试。在该技术中，可以交替地以10 Hz的频率将循环油压施加到两个样本表面。经过一些位移和应变测量的验证测试后，使用此新开发的测试技术对316型奥氏体不锈钢试样进行了初步测试。结果，通过将疲劳寿命定义为因破裂而导致油压突然下降的循环数，SBF测试结果（SN曲线）与常规疲劳测试非常吻合。