Cyclic viscoplasticity testing and modeling of a service-aged P91 steel

Hyde, Christopher J.; Sun, Wei; Hyde, T.H.; Rouse, J.P.; Farragher, T.; O'Dowd, Noel P.; Leen, S.B.

Abstract

A service-aged P91 steel was used to perform an experimental program of cyclic mechanical testing in the temperature range of 400 °C–600 °C, under isothermal conditions, using both saw-tooth and dwell (inclusion of a constant strain dwell period at the maximum (tensile) strain within the cycle) waveforms. The results of this testing were used to identify the material constants for a modified Chaboche, unified viscoplasticity model, which can deal with rate-dependant cyclic effects, such as combined isotropic and kinematic hardening, and time-dependent effects, such as creep, associated with viscoplasticity. The model has been modified in order that the two-stage (nonlinear primary and linear secondary) softening which occurs within the cyclic response of the service-aged P91 material is accounted for and accurately predicted. The characterization of the cyclic viscoplasticity behavior of the service-aged P91 material at 500 °C is presented and compared to experimental stress–strain loops, cyclic softening and creep relaxation, obtained from the cyclic isothermal tests.

Citation

Hyde, C. J., Sun, W., Hyde, T., Rouse, J., Farragher, T., O'Dowd, N. P., & Leen, S. (2014). Cyclic viscoplasticity testing and modeling of a service-aged P91 steel. Journal of Pressure Vessel Technology, 136(4), Article 044501. https://doi.org/10.1115/1.4026865

• Journal Article Type: Article
• Acceptance Date: Feb 14, 2014
• Online Publication Date: Apr 16, 2014
• Publication Date: Aug 1, 2014
• Deposit Date: Sep 19, 2017
• Journal: Journal of Pressure Vessel Technology
• Print ISSN: 0094-9930
• Electronic ISSN: 1528-8978
• Publisher: American Society of Mechanical Engineers
• Peer Reviewed: Peer Reviewed
• Volume: 136
• Issue: 4
• Article Number: 044501
• DOI: https://doi.org/10.1115/1.4026865
• Public URL: https://nottingham-repository.worktribe.com/output/994764
• Publisher URL: http://pressurevesseltech.asmedigitalcollection.asme.org/article.aspx?articleid=1832496
• Additional Information: Paper No: PVT-12-1136. Copyright © 2014 by ASME
• Contract Date: Sep 19, 2017