Critical View on the Creep Modelling Procedures

• Authors: L. Kloc
• Languages of publication: EN

Abstracts

EN

Process of creep deformation is rather complex, consisting of many interconnected subprocesses, mainly: (i) the creep strain itself, based on dislocation mobility as well as grain boundary activity, (ii) development of dislocation substructure (work strengthening and dynamic recovery), (iii) development of phase structure (phase transformations, precipitation, particle coarsening, etc.), and (iv) nucleation and development of voids and microcracks, i.e. creep damage. The creep experiments are time consuming and expensive, moreover, it is not possible to make experiments under the service conditions of particular materials due to very slow creep strain, the process seems to be ideal field for computer modelling. The experimental data are obviously available for the steady conditions only, so the effects of varying conditions during startup or shutdown of the components can be described by modelling. The model of creep deformation is obviously based on the so-called "creep constitutive equation", which should describe the strain rate dependence on stress, temperature and some other variables. Nevertheless, the comprehensive physical description of all the above mentioned processes is still missing. This paper should illustrate the shortcomings of most "creep constitutive equations", confronting them to some experimental results on common structural materials under non-steady loading conditions.

Keywords

EN

62.20.Hg; 87.10.Kn; 81.40.Lm

Discipline

• 62.20.Hg: Creep
• 87.10.Kn: Finite element calculations
• 81.40.Lm: Deformation, plasticity, and creep(see also 83.50.-v Deformation and flow in rheology)

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2015
• Volume: 128
• Issue: 4
• Pages: 540-542

Dates

published

2015-10

Contributors

author

L. Kloc

• Institute of Physics of Materials AS CR, v.v.i, Žižkova 22, 61662 Brno, Czech Republic

References

• [1] R.K. Penny, D.L. Marriott, Design for Creep, McGraw-Hill, London 1971, p. 192
• [2] L. Kloc, V. Sklenička, J. Ventruba, Mater. Sci. Eng. A 319-321, 774 (2001), doi: 10.1016/S0921-5093(01)00943-1
• [3] K. Milička, F. Dobeš, Eng. Mech. 5, 165 (1998)
• [4] L. Kloc, V. Sklenička, Mater. Sci. Eng. A 387-389, 633 (2004), doi: 10.1016/j.msea.2003.12.078
• [5] L. Kloc, J. Phys. Conf. Series 240, 012086 (2010), doi: 10.1088/1742-6596/240/1/012086

Identifiers

DOI

10.12693/APhysPolA.128.540