Cyclic plastic strain based damage tolerance for railway axles in China. (December 2016)

• Record Type: Journal Article
• Authors: Wu, S.C.; Zhang, S.Q.; Xu, Z.W.; Kang, G.Z.; Cai, L.X.
• Is Part Of: International journal of fatigue. Volume 93:Part 1(2016)
• Page Start: 64
• Page End: 70
• Publication Date: 2016-12
• Subjects: China high-speed railway train -- Fatigue crack propagation model -- Low cycle fatigue behavior -- Crack-tip blunting -- Plasticity-induced crack closure; Materials -- Fatigue -- Periodicals; Materials -- Fatigue; Periodicals; 620.1122
• DOI: 10.1016/j.ijfatigue.2016.08.006
• Languages: English
• ISSNs: 0142-1123

Abstract

Highlights: A low cycle fatigue based FCG is proposed in terms of RKE field and plastic strain energy. Variable stress ratios and crack closure can be rebuilt by improving the crack opening function. Proposed LowGRO model can well predict the FCG curve in structural materials compared with published PSE-RKE. Abstract: Railway axle is one of the most important safety critical components usually operated over a service life of 30 years or more in the order of 10 9 cyclic loading. Therefore, any derailment caused by fatigue damage should be rigorously inspected, assessed and repaired in both routine and emergence maintenance. By considering the effects of crack closure and load ratio, based on plastic strain energy and modified Rice-Kujawski-Ellyin solution in the tip of a growing fatigue crack under plane stress condition, a new crack closure based fatigue crack growth rate model entitled LowGRO has been proposed in terms of low cycle fatigue behavior and improved threshold stress intensity factor range at different loading ratios. For the railway axle used steel 25CrMo4, 34CrNiMo6 and open-reported structural materials, predicted results of current LowGRO are in good agreement with the experimental data. The LowGRO provides a potential compliment during the damage tolerance design like standard NASGRO equation commonly used for high-speed railway axles.