The effect of pre-corrosion by salt spray on the extremely-low cycle fatigue performance of HRB400E steel was studied. The steel samples were firstly subjected to salt spray corrosion with NaCl solution for 30~90 days, and then subjected to extremely-low cycle fatigue test via an axial displacement control facility to simulate the strong earthquake loading. Therewith, the relationship between the loading and cycle numbers, as well as the strain-life curves were obtained. Finally, the fracture faces were characterized by scanning electron microscope （SEM）。 The results show that the decline rates of life after pre-corrosion for 30 days, 60 days and 90 days were 4.4%~10.2%, 14.3%~31.8% and 7.8%~30%, respectively. The crack initiation life accounts for 90% of the total life, and the strain amplitude of 3% is the turning point between ultra-low cycle and low cycle fatigue. Salt spray corrosion has no obvious effect on the cyclic response characteristics and Masing characteristics of the test material. At last, the fracture zone was crescent-shaped along the edge of the test material. Longer salt spray corrosion time and higher strain amplitude would lead to dimples in the final fracture zone.
CHEN Lifei, LUO Yunrong, ZHANG Yingqian, LI Hui, LI Xiulan, LIAO Wenli. Effect of Pre-corrosion by Salt Spray on Extremely Low Cycle Fatigue Performance of HRB400E Seismic Steel Bar. Earth Science[J], 2021, 35（2）： 101-109 DOI:10.11901/1005.3093.2020.409