PSI - Issue 5

G. Lesiuk et al. / Procedia Structural Integrity 5 (2017) 904–911 Lesiuk et al./ Structural Integrity Procedia 00 (2017) 000 – 000

911

8

are observed with the increasing (Fig. 5a) tendency in low  K values (<20MPa m 1/2 ) for both materials. In case of the incorporation of the crack closure phenomenon (Fig. 5b), the distances between closure affected ( R =0.1) and closure reduced ( R =0.5) effect is decreased. But for three different R-ratios (0.1, 0.5, 0.75) the differences are vanishing in case of the da/dN diagram constructed with the  H basis (Fig. 6a). Fig.6b also shows the da/dN diagram constructed with the  J basis cyclic bending and two different R -ratios (0, 0.5).

4. Conclusions

1. The applied empirical formulas including  H and  J parameters range are good to description of fatigue crack growth rate in the tested materials. 2. It has been shown that the applied  H and  J parameters as compared with the parameter  K for different stress ratios R more precise describe crack growth rate, since they take more tested materials data (information) into account.

References

ASTM E647-15a - Standard test methods for fatigue crack growth rate, ASTM. Correia J.A.F.O., Abílio M.P. De Jesus, Alfonso Fernández-Canteli, Local unified probabilistic model for fatigue crack initiation and propagation: Application to a notched geometry, Engineering Structures, Volume 52, 2013, Pages 394-407, ISSN 0141-0296, http://dx.doi.org/10.1016/j.engstruct.2013.03.009. Correia J.A.F.O., S. Blasón, A.M.P. De Jesus, A.F. Canteli, P.M.G.P. Moreira, Paulo J. Tavares, Fatigue life prediction based on an equivalent initial flaw size approach and a new normalized fatigue crack growth model, Engineering Failure Analysis, Volume 69, November 2016, Pages 15-28, ISSN 1350-6307, https://doi.org/10.1016/j.engfailanal.2016.04.003. Dowling N.E., Begley J. A., 1976. Fatigue crack growth during gross plasticity and the J - integral,” in: ASTM STP 590, 82– 103. Forman R.G., V. E. Kearney, Engle R. M., 1967. Nunierical analysis of crack propagation in cyclic loaded structures. J. Basic Eng., Trans. ASME 89, 459-463. Lesiuk G., Szata M., José A.F.O. Correia, A.M.P. De Jesus, Filippo Berto, Kinetics of fatigue crack growth and crack closure effect in long term operating steel manufactured at the turn of the 19th and 20th centuries, Engineering Fracture Mechanics, Available online 26 April 2017, ISSN 0013-7944, https://doi.org/10.1016/j.engfracmech.2017.04.044. Manson S.S., 1966. Interfaces between fatigue, creep, and fracture. Int. J. Fract. Mech. 2, 327 – 363. Noroozi A.H, Glinka G, Lambert S. 2005. A two parameter driving force for fatigue crack growth analysis. Int J Fatigue 27, 1277 – 96. Noroozi AH, Glinka G, Lambert S., 2007. A study of the stress ratio effects on fatigue crack growth using the unified two-parameter fatigue crack growth driving force. Int J Fatigue 29, 1616 – 33. Ostash O.P., V. V. Panasyuk, I. M. Andreiko, R. V. Chepil’, V. V. Kulyk, and V. V. Vira, 2007. Methods for the construction o f the diagrams of fatigue crack-growth rate of materials, Materials Science 43(4). Paris P. C., Erdogan F., 1960. A critical analysis of crack propagation laws. J. of Basic Eng., Trans. ASME 85, 528-534. Rozumek D., 2009. Influence of the slot inclination angle in FeP04 steel on fatigue crack growth under tension. Materials & Design 30(6), 1859 1865. Rozumek D., Macha E., 2009. J-integral in the description of fatigue crack growth rate induced by different ratios of torsion to bending loading in AlCu4Mg1. Materialwissenschaft und Werkstofftechnik 40(10), 743-749. Rozumek D., Marciniak Z., 2011. Fatigue crack growth in AlCu4Mg1 under nonproportional bending with torsion loading. Materials Science 46, (5), 685-694. Rozumek, D., 2014. Survey of Formulas Used to Describe the Fatigue Crack Growth Rate. Materials Science 49(6), 723-733. Szata M., 2002. Modeling of fatigue crack growth using energy method (in Polish), Publishing House of Wroclaw University of Technology, Poland, Wroclaw. Szata M., Lesiuk G., 2009. Lifetime evaluation of element with fatigue crack using equivalent surface method / M. Szata, G. Lesiuk. W: Mehanika rujnuvannâ materialiv i micnist' konstrukcij / pid red. V. V. Panasûka. L'viv : Fiziko-mehanicnij Institut im. G. V. Karpenka NAN Ukraïny, s. 341-346. Szata M., Lesiuk G., algorithms for the estimation of fatigue crack growth using energy method, Archives of Civil and Mechanical Engineering, Volume 9, Issue 1, 2009, Pages 119-134, ISSN 1644-9665, https://doi.org/10.1016/S1644-9665(12)60045-4. Walker K., 1970. The effect of stress ratio during crack propagation and fatigue for 2024-T3 and 7075-TO Aluminum. ASTM STP 462, 1-14.