Issue 37

C. Brugger et alii, Frattura ed Integrità Strutturale, 37 (2016) 46-51 DOI: 10.3221/IGF-ESIS.37.07 51 C ONCLUSION AND PROSPECTS new ultrasonic fatigue testing device generating a biaxial proportional stress state with a positive loading ratio has been presented. VHCF tests were performed on a cast aluminum alloy already tested in the literature in HCF regime under a similar stress state. The new results are consistent with data from the literature. Self-heating is moderate, but the stop criterion could be improved to detect smaller crack. Crack initiation will be investigated, as two competing parameters play a role: the biaxial stress state which is maximal on the surface, and the possible presence of subsurface defects in a cast material. R EFERENCES [1] Bathias, C., Paris, P.C., Gigacycle Fatigue in Mechanical Practice, Marcel Dekker, New York, (2005). [2] Palin-Luc, T., Perez-Mora, R., Bathias, C., Dominguez, G., Paris P.C., Arana, J-L., Fatigue crack initiation and growth on a steel in the very high cycle regime with sea water corrosion, Engng Fract. Mechanics, 77 (2010) 1953–1962. doi:10.1016/j.engfracmech.2010.02.015 [3] Perez-Mora, R., Palin-Luc, T., Bathias, C., Paris, P.C., Very high cycle fatigue of a high strength steel under sea water corrosion: A strong corrosion and mechanical damage coupling, Int. J. Fatigue, 74 (2015) 156–165. doi:10.1016/j.ijfatigue.2015.01.004 [4] Mason, W.P., Piezoelectric Crystals and their application in ultrasonics, Van Nostrand, New York, (1956), 161. [5] Bathias, C., Piezoelectric fatigue testing machines and devices, Int. J. Fatigue, 28 (2006) 1438–1445. doi:10.1016/j.ijfatigue.2005.09.020 [6] Mason W.P., Ultrasonic fatigue, in: J.M. Well, O.L.D. Buck Roth, J.K. Tien (Eds.), Proceedings of the First International Conference on Fatigue and Corrosion Fatigue Up to Ultrasonic Frequencies, The Metallurgical Society of AIME (1982) 87–102. [7] Stanzl-Tschegg, S.E., Mayer, H. R., Tschegg, E. K., High frequency method for torsion fatigue testing, Ultrasonics, 31 (1993) 275–280. doi:10.1016/0041-624X(93)90021-Q [8] Mayer, H., Ultrasonic torsion and tension–compression fatigue testing: Measuring principles and investigations on 2024-T351 aluminium alloy, Int. J. Fatigue, 28 (2006) 1446–1455. doi:10.1016/j.ijfatigue.2005.05.020 [9] Nikitin, A., Bathias C., Palin-Luc, T., A new piezoelectric fatigue testing machine in pure torsion for ultrasonic gigacycle fatigue tests: application to forged and extruded titanium alloys, Fat. Frac. Engng. Mat. Structures, 38 (2015) 1294–1304. doi:10.1111/ffe.12340 [10] Wagner, D., Cavalieri, F.J., Bathias, C., Ranc, N., Ultrasonic fatigue tests at high temperature on an austenitic steel, Propulsion Power Research, 1 (2012) 29–35. doi:10.1016/j.jppr.2012.10.008 [11] Blanc, M., Osmond, P., Palin-Luc, T., Bathias C., French patent N° FR1357198 (2013). [12] Koutiri, I., Effet des fortes contraintes hydrostatiques sur la tenue en fatigue des matériaux métalliques, PhD thesis, ENSAM, N° 2011-ENAM-0015 (2011). [13] Koutiri, I., Bellett, D., Morel, F., Augustins, L., Adrien, High cycle fatigue damage mechanisms in cast aluminium subject to complex loads, Int. J. Fatigue, 47 (2013) 44–57. doi:10.1016/j.ijfatigue.2012.07.008 [14] Koutiri, I., Morel, F., Bellett, D., Augustins, L, Effect of high hydrostatic stress on the fatigue behavior of metallic materials, ICF-12, 5 (2009) 3694–3703. [15] Dang-Van, K., Cailletaud, G., Flavenot, J.F., Douaron, L., Lieurade, H.P, in: M. Brown, K. Miller (Eds), Biaxial and multiaxial fatigue, ESIS, Sheffield, (1989) 459–478. [16] Crossland, in: Int. Conf. on Fat. of Metals (London, 1959), Inst. of. Mech. Eng., 138–149. A