Thermal-mechanical fatigue simulation of a P91 steel in a temperature range of 400–600°C

Abstract

A note on versions:The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription.For more information, please contact eprints@nottingham.ac.uk 1 Thermal-mechanical fatigue simulation of a P91 steel in a temperature range of 400-600˚C AbstractThis paper deals with the identification of material constants to simulate the effect of cyclic mechanical loading and temperatures. A Chaboche viscoplasticity model was used in this study to model the thermal-mechanical behaviour of a P91 martensitic steel. A fully-reversed cyclic mechanical testing programme was conducted isothermally between 400 and 600˚C with a strain amplitude of 0.5%, to identify the model constants using a thermo-mechanical fatigue (TMF) test machine. Thermo-mechanical tests of P91 steel were conducted for two temperature ranges of 400 to 500˚C and 400 to 600˚C. From the test results, it can be seen that the P91 steel exhibits cyclic softening throughout the life of the specimens, for both isothermal and thermal-mechanical loading and this effect can be modelled by the set of viscoplasticity constants obtained. Finite element simulations of the test specimens show good comparison to isothermal and TMF experimental data.

Multiaxial cyclic viscoplasticity model for high temperature fatigue of P91 steel

“…This result is consistent with previous work. 12,14 As the cycles increase, the stress from an initial peak distribution ( N = 1), reduces owing to the cyclic softening behaviour of P91 steel, 7,24 as illustrated in Figs. 5 and 7.…”

“…where Z and n are the power law cyclic viscoplastic material parameters, obtained from the literature 7 and f is defined by equation ( 5). In Fig.…”

“…P91 steel is a 9Cr martensitic steel typically used for plant header and piping systems owing to its high creep strength. 3 A number of material models capable of simulating the constitutive behaviour of candidate materials already exist, including the unified Chaboche model [4][5][6][7] and the two-layer viscoplasticity model. 8,9 However, a hyperbolic sine material model has been chosen as it is more representative of the key mechanisms of deformation, 10 enabling strain-rate independence of the material parameters and offers greater accuracy through the full stress regime.…”

Viscoplastic constitutive model considering strain rate sensitivity under multiaxial thermomechanical fatigue loading

“…The first term χ 0 1 of the back stress deviator χ 0 expresses the rapid inelastic deformation in the small inelastic strain region, while the second term χ 0 2 expresses the steady-state inelastic behavior in the large inelastic strain region. 79,80 The kinematic hardening rule can describe the movement of the yield surface, which means that the Bauschinger effect of the material under fatigue loading can be characterized.…”

Simulation of low cycle fatigue stress‐strain response in 316LN stainless steel using non‐linear isotropic kinematic hardening model—A comparison of different approaches

“…Similar predictions of stabilized hysteresis loop and CSR have been reported using Chaboche model in austenitic stainless steels, ferritic steels, and superalloys. [27][28][29][30][31][32] In some of these studies, 13,32,33 the predictions have been significantly improved by adopting the optimization procedures in determining the model parameters of cyclic plasticity and viscoplasticity models.…”