Simulation of fatigue crack growth by crack tip blunting

0044942 - ÚFM 2007 RIV NL eng C - Conference Paper (international conference)
Hutař, Pavel - Sauzay, M.
Simulation of fatigue crack growth by crack tip blunting.
[Simulace šíření únavových trhlin vlivem plasticity.]
Fracture of Nano and Engineering Materials and Structures : proceedings. Dordrecht: Springer, 2006 - (Gdoutos, E.), s. 1-8. ISBN 1-4020-4971-4.
[European Conference of Fracture /16./. Alexandroupolis (GR), 03.07.2006-07.07.2006]
R&D Projects: GA ČR GP106/06/P239
Institutional research plan: CEZ:AV0Z20410507
Keywords : plastic blunting * fatigue crack
Subject RIV: JL - Materials Fatigue, Friction Mechanics

A study of fatigue crack growth due to blunting and re-sharpening of a crack tip is proposed in this article. The numerical modeling is based on elastic-plastic finite element analysis using the CASTEM code. On the model of the long cracks, in a semi-infinite plate, the possibility of reasonable prediction of fatigue crack growth due to crack tip blunting mechanism was studied. A parametric study of the influence of the yield stress of material on fatigue crack growth was made. The crack propagation rate was found to be proportional to the amplitude of the crack tip opening displacement in the usual range of the stress intensity factor (corresponding to small scale yielding conditions). Two different experimentally obtained sets of fatigue crack growth data (316LN and P91 steel) were used for comparison with the numerical predictions.

V práci jsou uvedeny možnosti numerické simulace šíření únavových trhlin pomocí plastického otupení na čele trhliny. Modelování bylo provedeno v konečnoprvkovém systému CASTEM. Výsledky byly porovnány s experimentálními výsledky získanými na ocelích užívaných v jaderné energetice 316LN a P91.
Permanent Link: http://hdl.handle.net/11104/0137606