Unified viscoplastic constitutive model for fatigue-creep interaction of 9-12% Cr steel at high temperature
The fatigue-creep interaction behavior of high temperature materials is of increasing interest both in terms of the complex cyclic deformation response and the constitutive modeling.A series of isothermal, strain-controlled low cycle fatigue and fatigue-creep tests at 625℃ were conducted for 9Cr0.5M1.8WVNb steel.Compared to low cycle fatigue, an accelerated cyclic softening phenomenon was observed in fatigue-creep loading condition due to additional inelastic strain appearing during the dwell period, especially in the initial cycles of the fatigue life.Cyclic stress relaxation declined cycle by cycle due to cyclic softening, and then saturated until failure.Based on the combined isotropic and nonlinear kinematic hardening rules of Chaboche with several added features for strain ra nge dependence, static recovery and cyclic stress relaxation, a robust cyclic viscoplastic constitutive model was developed for addressing the fatigue-creep interaction at high temperature.The simulation capability of the developed model was also veri fied by the experimental data obtained from the tests.
fatigue-creep interaction visocoplastic constitutive model static recovery cyclic stress relaxation
Shang-Lin Zhang Fu-Zhen Xuan Su-Juan Guo
Key Laboratory of Pressure System and Safety, MOE;School of Mechanical and Power Engineering;East China University of Science and Technology, Shanghai 200237, P.R China
国际会议
长沙
英文
27-32
2016-10-16（万方平台首次上网日期，不代表论文的发表时间）