Cyclic Deformation Experiment and Constitutive Model of High-speed Railway Gear Steel 18CrNiMo7-6

ZHAO Wenjie, YANG Shaopu, REN Xuehong, WEN Guilin


To study the cyclic softening/hardening behavior of high-speed railway gear steel 18CrNiMo7-6, RPL 100 electronic creep fatigue tester was used to carry out the uniaxial symmetrical strain cycling experiments on the gear steel under different strain amplitudes. Then, the ratchetting behaviour of gear steel 18CrNiMo7-6 under different stress conditions was tested to study the ratchetting evolution of gear steel under asymmetric stress cycling. The results show that the gear steel (18CrNiMo7-6) exhibits the cyclic softening characteristics under strain cycling and exhibits two stages of decaying ratcheting strain rate and constant ratcheting strain rate under asymmetric stress cycling. Then,a modified elasto-plastic cyclic constitutive model was established by introducing the evolution equation of ratchetting parameters related to the cumulative plastic strain into the Ohno-Abdel-Karim nonlinear kinematic hardening rule. The simulated results show that the model can reasonably predict the cyclic softening characteristics and the ratchetting evolution of gear steel (18CrNiMo7-6).



Keywords:   high-speed railway gear steel,  cyclic softening,  ratchetting behaviour , constitutive models

Full Text:



ZHU Y L,KANG G Z,YU C. A finite cyclic elasto -plastic constitutive model to improve the description of cyclic stress-strain hysteresis loops [J]. International Journal of Plasticity,2017,95: 191—215.

CHABOCHE J L,NOUAILHAS D. Constitutive modeling of ratchetting effects,part I:experimental facts and properties of the classical models [J]. Journal of Engineering Materials & Technology,1989,111 (4):384—392.

QIU B,KAN Q H,LIU Y J,et al. Experiment and simulation on the biaxial compression -torsion ratchetting behavior of high strength rail steel[J]. Engineering Mechanics,2015,32 (7):229—235. (In Chinese)

ZHAO W J,YANG S P,WEN G L,et al. Fractional-order visco- plastic constitutive model for uniaxial ratcheting behaviors[J]. Applied Mathematics and Mechanics,2019,40 (1):49—62.

FREDERICK C O ,ARMSTRONG P J . A mathematical representation of the multiaxial Bauschinger effect [J]. Materials at High Temperatures,2007,24 (1):1—26.

CHABOCHE J L. On some modifications of kinematic hardening to improve the description of ratchetting effects [J]. International Journal of Plasticity,1991,7 (7):661—678.

OHNO N,WANG J D. Kinematic hardening rules with critical state of dynamic recovery,part :application to experiments of ratchetting behavior[J]. International Journal of Plasticity,1993,9 (3):391—403.

JIANG Y Y,SEHITOGLU H. Cyclic ratchetting of 1070 steel under multiaxial stress states [J]. International Journal of Plasticity, 1994,10 (5):579—608.

ABDEL-KARIMM ,OHNO N . Kinematic hardening model suitable for ratchetting with steady -state [J]. International Journal of Plasticity,2000,16 (3/4):225—240.

KANG G,OHNO N,NEBU A. Constitutive modeling of strain range dependent cyclic hardening [J]. International Journal of Plasticity, 2003,19 (10):1801—1819.

WU D L,XUAN F Z,GUO S J,et al. Uniaxial mean stress relaxation of 9% ~12% Cr steel at high temperature:experiments and viscoplastic constitutive modeling [J]. International Journal of Plasticity,2016,77:156—173.

CHABOCHE J L,NOUAILHAS D. Constitutive modeling of ratchetting effects,part :possibilities of some additional kinematic rules[J]. Journal of Engineering Materials& Technology, 1989,111 (4):384—416.

CHABOCHE J L. A review of some plasticity and viscoplasticity constitutive theories[J]. International Journal of Plasticity,2008,24 (10):1642—1693.


  • There are currently no refbacks.