Low Cycle Fatigue Behavior of S550 High-Strength Steel under Different Strain Ratios
This study investigates the low-cycle fatigue(LCF)behavior of the high strength steel S550 based on the standard coupon specimens under different strain amplitudes with different strain ratios at room temperature.The test results characterize the cyclic stress-strain relationship,mean stress relaxation behavior and LCF related cyclic plasticity parameters of S550.The high strength steel investigated in this paper exhibits cyclic softening behavior until failure.The stable hysteresis loops under different strain amplitudes at half of fatigue life indicates a non-Masing behavior.Under asymmetrical strain-controlled test,S550 shows a rapid mean stress relaxation behavior that the positive mean stress relaxes to zero with 10%of fatigue life.Complementary,the effect due to the different strain ratios on the total fatigue life for all the specimens is small under the investigated strain amplitudes.Finally,this paper presents an energy-based model for predicting the low cycle fatigue life of this high strength steel.The energy model is based on the product of the stress amplitude and strain amplitude at the first cycle considering the constant cyclic softening ratio of this material.
low-cycle fatigue mean stress relaxation high strength steel cyclic plasticity energy-based model
Liuyang Feng Xudong Qian
Department of Civil and Environmental Engineering,Centre for Offshore Research and Engineering,National University of Singapore,Singapore 117576
国际会议
海口
英文
85-86
2018-01-12（万方平台首次上网日期，不代表论文的发表时间）