Constraint aspects of the evaluation of fatigue test results in Paris region

0045423 - ÚFM 2007 RIV SK eng J - Journal Article
Knésl, Zdeněk - Hutař, Pavel - Seitl, Stanislav
Constraint aspects of the evaluation of fatigue test results in Paris region.
[Vliv constraintu na stanovení únavových charakteristik v Parisově oblasti.]
Komunikácie. Roč. 8, č. 4 (2006), s. 25-28. ISSN 1335-4205
R&D Projects: GA ČR GP101/04/P001; GA ČR GP106/06/P239
Institutional research plan: CEZ:AV0Z20410507
Keywords : constraint * T-stress * fatigue crack growth
Subject RIV: JL - Materials Fatigue, Friction Mechanics

The growth of the fatigue crack is depending on the crack growth resistance of the material as a bulk property. The fatigue crack growth properties of a material are usually described by the correlation between crack propagation rate, and corresponding range of the stress intensity factor (Paris-Erdogan law). Formulated modified Paris-Erdogan law estimate quantitatively the changes of the fatigue crack propagation rate due to different level of constraint. In-plain constraint was described by T-stress value. The validity of the approach suggested has been proved by the comparison of measured and calculated values of the crack propagation rate and it was found that experimental values correspond well with those numerically predicted. The results presented makes it possible to relate experimentally measured data obtained from specimens with different geometries and thus contribute to more reliable estimates of residual fatigue life of structures.

V článku je poukázáno na možnost eliminace závislosti experimentálních dat na geometrii tělesa a diskutována otázka přenositelnosti těchto dat z malých laboratorních vzorků na velká tělesa. Je zdůrazněn význam constraintu pro zvýšení spolehlivosti odhadů životnosti těles s trhlinami.
Permanent Link: http://hdl.handle.net/11104/0137948