| Autor: |
J. Monnet, Y. Gaillard, F. Richard, M. Personeni, S. Thibaud |
| Jazyk: |
angličtina |
| Rok vydání: |
2024 |
| Předmět: |
|
| Zdroj: |
Journal of Materials Research and Technology, Vol 28, Iss , Pp 1370-1381 (2024) |
| Druh dokumentu: |
article |
| ISSN: |
2238-7854 |
| DOI: |
10.1016/j.jmrt.2023.12.071 |
| Popis: |
Determining toughness properties is crucial for the development of components made of brittle materials, especially at the microscale. Numerous methods rely on establishing a limit load that triggers the propagation of a pre-cracked specimen. The primary challenge lies in accurately and repeatably determining this limit load value. In this study, we introduce a coupled numerical-experimental approach to determine the stress intensity factor at the microscale using a micro-bending test on pre-notched cemented carbide micro-cantilevers. Specimens are fabricated through micro-electrical-discharge milling, and the initial crack is generated using a focused ion beam process to ensure a repeatable crack shape. Geometries are defined to validate beam theories.Cycling bending tests, employing nanoindentation with three types of loading (fatigue-like, progressive repeated, and ramping sinusoidal loadings), are utilized to ascertain fracture toughness properties of tungsten carbide material at the microscale. Micro-indentation is also conducted conventionally to compare hardness at meso and micro-scales. Analytical methods and finite element analysis are employed to extract the critical stress intensity factor. The cyclic bending test with the proposed ramping sinusoidal loading demonstrates a time shift between the applied force and the displacement, enabling accurate and repeatable detection of the initiation of crack propagation. The primary contributions are associated with the development of a micro-bending test on precracked microcantilevers with ramping sinusoidal loading applied by a nanoindentor device. The miniaturization of specimens and tests, for an equivalent grain size, does not result in a scale effect on toughness properties. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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