PSI - Issue 7

M. Wicke et al. / Procedia Structural Integrity 7 (2017) 235–241 M. Wicke et Al./ Structural Integrity Procedia 00 (2017) 000–000

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dominated crack extension of long cracks is possible even at a stress ratio of R = 0.1, if the load amplitude is small enough. Both mechanism were found to keep the crack from continuous extension. In order to gain additional information on the crack propagation behavior at R = 0.1 and for a detailed comparison of the mechanisms affecting the crack extension at a stress ratio of R = 0.1 with that at R = -1 described in [Stein et al. (2017)], it is worthwhile to analyze the fracture surfaces and crack tip fields in following studies. Acknowledgements The authors would like to thank the German Research Foundation (DFG) for financial support. References Forth, S.C., Newman, J.C., Forman, R.G., 2003. On generating fatigue crack growth thresholds. International Journal of Fatigue 25, 9-15. Lafarie-Frenot, M.C., Gasc, C., 1983. The influence of age-hardening of fatigue crack propagation behavior in aluminium alloy in vacuum. Fatigue & Fracture of Engineering Materials & Structures 6, 329-344. Newman, J.C., Schneider, J., Daniel, A., McKnight, D., 2005. Compression pre-cracking to generate near-threshold fatigue-crack-growth rates in two aluminum alloys. International Journal of Fatigue 27, 1432-1440. Newman, J.C., Yamada, Y., 2010. Compression precracking methods to generate near-threshold fatigue-crack-growth-rate data. International Journal of Fatigue 32, 879-885. Nishida, T., Pezzotti, G., Mangialardi, T., Paolini A.E., 1996. Fracture mechanics evaluation of ceramics by stable crack propagation in bend bar specimens. In: Bradt, R.C., Hasselman, D.P.H., Munz, D., Sakai, M., Shevchenko, V.Y. (Eds.). Fracture Mechanics of Ceramics 11, 107-114. Pippan, R., 1987. The growth of short cracks under cyclic compression. Fatigue & Fracture of Engineering Materials & Structures 9, 319-328. Pippan, R., Plöchl, L., Klanner, F., Stüwe, H.P., 1994. The use of fatigue specimens precracked in compression for measuring threshold values and crack growth. Journal of testing and evaluation 22, 98-103. Stein, T., Wicke, M., Brueckner-Foit, A., Kirsten, T., Zimmermann, M., Buelbuel, F., Christ, H.-J., 2017. Crack growth behavior in an aluminum alloy under very low stress amplitudes. Journal of Materials Research, 1-8. doi:10.1557/jmr.2017.274 Suresh, S., Vasudevan, A.K., Bretz, P.E., 1984. Mechanisms of slow fatigue crack growth in high strength aluminum alloys: role of microstructure and environment. Metallurgical and Materials Transactions A 15, 369-379. Vasudevan, A.K., Suresh, S., 1982. Influence of corrosion deposits on near-threshold fatigue crack growth behavior in 2xxx and 7xxx series aluminum alloys. Metallurgical and Materials Transactions A 13, 2271-2280.