A continual model of damaged media for describing the creep failure process

I. A. Volkov ; L. A. Igumnov ; S. Yu. Litvinchuk

Učënye zapiski Kazanskogo universiteta. Seriâ Fiziko-matematičeskie nauki, Uchenye Zapiski Kazanskogo Universiteta. Seriya Fiziko-Matematicheskie Nauki, Tome 161 (2019) no. 4, pp. 509-525

Résumé

The main laws of deformation and degradation processes of the initial strength properties of structural materials (metals and their alloys) according to the long-term strength mechanism were considered. From the viewpoint of the mechanics of damaged media (MDM), a mathematical model was created to describe inelastic deformation and damage accumulation during the creep process. An experimental and theoretical methodology for determining material parameters of the derived defining relations of MDM was developed. The material parameters and scalar functions of the MDM model, its reliability and the scope of its applicability were determined based on the analysis of the processes of deformation and failure of laboratory specimens in the conditions of soft loading (controlled stresses). The results of the experimental study of short-term creep of the VZh-159 heat-resistant alloy were presented. The process of deformation and damage accumulation was numerically analyzed; the obtained numerical results were compared with the data of the full-scale experiments. Comparison of the numerical and experimental data shows that the introduced defining relations of MDM adequately describe the response of materials in the conditions of degradation of the initial strength properties of structural materials according to the long-term strength mechanism.

Détail

Keywords: nonstationary creep, long-term strength, defining relations, mechanics of damaged media, temperature, damage, material parameter, numerical experiment, full-scale experiment.
Mots-clés : simulation

Bibliographie

[1] Mitenkov F. M., Kaidalov V. F., Korotkikh Yu.G., Methods of Substantiation of Nuclear Power Plants' Life, Mashinostroenie, M., 2007, 448 pp. (In Russian)

[2] Volkov I. A., Korotkikh Yu.G., Equations of the State for the Viscoelasticoplastic Media with Defects, Fizmatlit, M., 2008, 424 pp. (In Russian)

[3] Lokoshchenko A. M., Creep and Long-Term Strength of Metals, Fizmatlit, M., 2016, 504 pp. (In Russian)

[4] Lemaitre J., “Damage modelling for prediction of plastic or creep fatigue failure in structures”, Trans. 5th Int. Conf. SMiRT-5, v. L, North Holland, Amsterdam, 1979, L5/1 b, 1–8

[5] Murakami S., “Mechanical description of creep damage and its experimental verification”, J. Mec. Theor. Appl., 1:5 (1982), 743–761 | Zbl

[6] Manson S. S., Ensign C. R., “A quarter-century of progress in the development of correlation and extrapolation methods for creep rupture data”, J. Eng. Mater. Technol., 101:4 (1979), 317–325 | DOI

[7] Le May I., “Developments in parametric methods for handling creep and creep-rupture data”, J. Eng. Mater. Technol., 101:4 (1979), 326–330 | DOI

[8] Larson F. R., Miller J. A., “A time-temperature relationship for rupture and creep stresses”, Trans. ASME, 74:5 (1952), 539–605

[9] Nikitenko A. F., “Experimental verification of the hypothesis of the existence of surface creep under complex loading conditions. Report No. 1”, Strength Mater., 16:8 (1984), 1063–1068 | DOI

[10] Nikitenko A. F., “Experimental verification of the hypothesis of the existence of surface creep under complex loading conditions. Report No. 2”, Strength Mater., 16:8 (1984), 1069–1071 | DOI

[11] Woodford D. A., “Creep damage and the remaining life concept”, J. Eng. Mater. Technol., 101:4 (1979), 311–316 | DOI

[12] Volkov I. A., Igumnov L. A., Korotkikh Yu. G., Applied Theory of Viscoplasticity, Izd. NNGU, Nizhny Novgorod, 2015, 318 pp. (In Russian)

[13] Volkov I. A., Igumnov L. A., Kazakov D. A., Shishulin D. N., Smetanin I. V., “Constitutive relations of unsteady creep in a complex stress state”, Probl. Prochn. Plast., 78:4 (2016), 436–451 (In Russian) | DOI

[14] Bodner S. R., Lindholm U. S., “An incremental criterion for time-dependent failure of materials”, J. Eng. Mater. Technol., 98:2 (1976), 140–145 | DOI

[15] Lemaitre J., “A continuous damage mechanics model for ductile fracture”, J. Eng. Mater. Technol., 107:1 (1985), 83–89 | DOI

[16] Perzyna P., “Constitutive modeling of dissipative solids for postcritical behavior and fracture”, J. Eng. Mater. Technol., 106:4 (1984), 410–419 | DOI

[17] Lokoshchenko A. M., “Criteria for determining the long-term strength under conditions of complex loading”, Strength Mater., 21:9 (1989), 1121–1124 | DOI

[18] Banthia V., Mukherjee S., “On an improved time integration scheme for stiff constitutive models of inelastic deformation”, J. Eng. Mater. Technol., 107:4 (1985), 282–285 | DOI

[19] Kapustin S. A., Kazakov D. A., Churilov Yu.A., Galushchenko A. I., Vakhterov A. M., “Experimental and theoretical study of the behavior of structural parts from heat-resistant alloy under high-temperature creep”, Probl. Prochn. Plast., 2008, no. 70, 100–111 (In Russian)

[20] Volkov I. A., Igumnov L. A., Kazakov D. A., Emel'yanov A. A., Tarasov I. S., Guseva M. A., “Software implementation of viscoplastic deformation and damage accumulation processes in structural alloys under thermal-mechanical loading”, Probl. Prochn. Plast., 78:2 (2016), 188–207 (In Russian) | DOI