Development of a small-punch-fatigue test method to evaluate fatigue strength and fatigue crack propagation

Autor: Yamazaki Yasuhiro, Yoshida Keisuke, Okada Kazuhiro, Arai Momoka, Nakahara Yosuke, Ota Yutaro
Jazyk: angličtina
Rok vydání: 2024
Předmět:
Zdroj: Journal of the Mechanical Behavior of Materials, Vol 33, Iss 1, Pp 391-9 (2024)
Druh dokumentu: article
ISSN: 2191-0243
DOI: 10.1515/jmbm-2024-0004
Popis: Herein, fatigue and crack propagation tests were conducted using the small-punch-fatigue (SPF) test to verify its applicability to assess fatigue strength and fatigue crack propagation behavior. During the SPF test, a fatigue crack first initiated at the specimen center and then propagated in the radial direction. In most cases, three fatigue cracks propagated from the specimen center to the radial direction in point symmetry. X-ray computed tomography revealed that the crack initiated by the SPF test had a quarter ellipse shape. Elastic finite element (FE) analysis was conducted to estimate the stress state and stress intensity factor (SIF) of the specimen, and an approximate equation was obtained as a function of the applied load. The experimental results comprising fatigue lives and crack growth rates obtained via the SPF test were compared with the conventional uniaxial test data as functions of the stress amplitude and SIF determined via elastic FE analysis, respectively. This comparison showed that the SPF test can be applied to the fatigue test and fatigue crack propagation test.
Databáze: Directory of Open Access Journals