PSI - Issue 7

Kentaro Wada et al. / Procedia Structural Integrity 7 (2017) 391–398 K. Wada et al./ Structural Integrity Procedia 00 (2017) 000–000

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4. Conclusions In this study, tension-compression fatigue tests were performed on the bearing steel, SAE52100. The crack closure behavior was investigated, in order to understand the effects of compressive mean stress on the fatigue crack threshold. The results are summarized as follows: 1. The obtained fatigue limits were in good agreement with a modified Goodman diagram at −5 ≤ R ≤ −1. On the other hand, at R = −10 , the fatigue limit was more than twice as high as the modified Goodman prediction, leading to the unexpected detection of a non-propagating crack. 2. A series of experimental results suggested that the peculiar, afore-mentioned phenomenon was caused by interaction between crack closure development during crack growth and the residual stress field, as generated by compressive yielding ahead of the notch root. References Fujii, Y., Maeda, K., Otsuka, A., 2001. A New Test Method for Mode II Fatigue Crack Growth in Hard Materials. Journal of the Society of Materials Science, Japan 50, 1108-1113. Hashimoto, S., Komata, H., Matsunaga, H., 2017. Effect of small defect on the flaking strength of rolling bearings (Part 1: FEM analyses of stress intensity factor K II under rolling contact). Transactions of the JSME (in Japanese) 83, 16-00584. Hashimoto, S., Komata, H., Matsunaga, H., 2017. Effect of small defect on the flaking strength of rolling bearings (Part 2: Evaluation of the flaking strength of rolling bearing having a small drilled hole based on stress intensity factor). Transactions of the JSME (in Japanese) 83, 16-00585. Komata, H., Yamabe, J., Fukushima, Y., Matsuoka, S., 2012. Proposal of Rolling Contact Fatigue Crack Growth Test Using a Specimen with a Small Artificial Hole. TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A 78, 1250-1265. Kondo, Y., Sakae, C., Kubota, M., Kudou, T., 2003. The effect of material hardness and mean stress on the fatigue limit of steels containing small defects. Fatigue & Fracture of Engineering Materials & Structures 26, 675-682. Matsunaga, H., Muramoto, S., Shomura, N., Endo, M., 2009. Shear Mode Growth and Threshold of Small Fatigue Cracks in SUJ2 Bearing Steel. Journal of the Society of Materials Science, Japan 58, 773-780. Matsunaga, H., Shomura, N., Muramoto, S., Endo, M., 2011. Shear mode threshold for a small fatigue crack in a bearing steel. Fatigue & Fracture of Engineering Materials & Structures 34, 72-82. Murakami, Y., 1985. Analysis of stress intensity factors of modes I, II and III for inclined surface cracks of arbitrary shape. Engineering Fracture Mechanics 22, 101-114. Murakami, Y., Fukuhara, T., Hamada, S., 2002. Measurement of Mode II Threshold Stress Intensity Factor Range Δ K IIth . Journal of the Society of Materials Science, Japan 51, 918-925. Nishizawa, H., Ogawa, T., 2005. Mode II Fatigue Crack Growth Characteristics and Experimental Evaluation of the Crack Driving Force. Journal of the Society of Materials Science, Japan 54, 1295-1300. Okazaki, S., Matsunaga, H., Ueda, T., Komata, H., Endo, M., 2014. A practical expression for evaluating the small shear-mode fatigue crack threshold in bearing steel. Theoretical and Applied Fracture Mechanics 73, 161-169. Okazaki, S., Wada, K., Matsunaga, H., Endo, M., 2017. The influence of static crack-opening stress on the threshold level for shear-mode fatigue crack growth in bearing steels. Engineering Fracture Mechanics 174, 127-138. Olver, A.V., 2005. The Mechanism of Rolling Contact Fatigue: An Update. Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 219, 313-330. Otsuka, A., Fujii, Y., Maeda, K., 2004. A new testing method to obtain mode II fatigue crack growth characteristics of hard materials. Fatigue & Fracture of Engineering Materials & Structures 27, 203-212. Pippan, R., 1987. The growth of Short Cracks Under Cyclic Compression. Fatigue & Fracture of Engineering Materials & Structures 9, 319-328. Yamabe, J., Kobayashi, M., 2007. Effect of Hardness and Stress Ratio on Threshold Stress Intensity Factor Ranges for Small Cracks and Long Cracks in Spheroidal Cast Irons. Journal of Solid Mechanics and Materials Engineering 1, 667-678.