On the assessment of train crankshafts fatigue life based on LCF tests and 2D-FE evaluation of J-integral

Ahmed Ktari (1, 2) , Nader Haddar (1) , Farhad Rezai-Aria (2) , Hassine Ferid Ayedi (1)

1 ENIS - École Nationale d'Ingénieurs de Sfax | National School of Engineers of Sfax
2 ICA - Institut Clément Ader

Low cycle fatigue (LCF) tests were carried out on forged carbon steel (AISI 4130) used in V12 Diesel engine crankshafts, at room temperature and 300 degrees C, under total strain control. These tests were performed in order to study the cyclic mechanical behavior, lifetime and damage mechanisms of the material. Then, a Chaboche nonlinear isotropic-kinematic hardening model available in the commercial FE code Abaqus was identified and a 2D-FE evaluation of J-integral, chosen as a crack driven force, has been carried out to estimate the crankshaft life under cyclic bending loads when a macroscopic crack propagates. It has been found that i) material lifetime was not affected by temperature at the studied domain, ii) the fractured surfaces examined with SEM exhibit typical features of ductile fracture behavior, and iii) the number of cycles spent until the total crankshaft fracture is relatively short compared to its total fatigue life. (C) 2016 Elsevier Ltd. All rights reserved.

Mots clés: Behavior law; J-integral; Fatigue behavior; Lifetime prediction; Fracture mechanisms

Domaines: Sciences de l'ingénieur [physics]

Ahmed Ktari, Nader Haddar, Farhad Rezai-Aria, Hassine Ferid Ayedi. On the assessment of train crankshafts fatigue life based on LCF tests and 2D-FE evaluation of J-integral. Engineering Failure Analysis, 2016, 66, pp.354-364. ⟨10.1016/j.engfailanal.2016.05.011⟩. ⟨hal-01599983⟩