High-temperature bending fatigue properties of oxide dispersion-strengthened platinum–rhodium alloy under high axial stress

• Published in: International journal of fatigue 2020-03, Vol.132, p.105385, Article 105385
• Main Authors: Niwa, A., Akita, Y., Enomoto, K., Aoyama, R., Akebono, H., Sugeta, A.
• Format: Article
• Language: English
• Subjects: Amplitudes; Axial stress; Bending fatigue; Creep; Creep analysis; Damage; Dispersion hardening alloys; Elastic analysis; Fatigue tests; Heat resistant alloys; High temperature; High temperature fatigue; Life prediction; Materials fatigue; Metal fatigue; Oxide dispersion strengthening; Platinum; Platinum base alloys; Rhodium; Tensile stress
• ISSN: 0142-1123; 1879-3452
• DOI: 10.1016/j.ijfatigue.2019.105385

•A higher test frequency corresponded to a higher number of cycles until failure.•At a low stress amplitude, the effect of the cyclic stress was small.•At a high stress amplitude, creep damage progressed only in the central part.•Elastic-plastic creep analysis also agreed well with the experimental results. In this study, high-temperature bending fatigue tests were carried out using an oxide dispersion-strengthened platinum-rhodium alloy at 1400 °C with a relatively high axial stress. At a low stress amplitude, creep damage progressed throughout the cross-section of the sample due to axial stress. However, at a high stress amplitude, creep damage progressed only in the central part of the direction of thickness and fracturing originated from inside the sample. Elastic-plastic creep analysis also indicated that high tensile stress remained inside the sample due to the yielding near the surface. The fact that the life is determined by the creep due to the stress generated inside of the material is useful for life prediction.