Open AccessStudy on fatigue crack growth rate of 15CrMo steel based on stress ratio and corrosion environment
Author(s) -
Jing Wang,
Chong Guo,
Kuichao Huang,
Xiaolin Shao
Publication year - 2020
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.179
H-Index - 26
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/508/1/012215
Subject(s) - crack closure , materials science , growth rate , corrosion fatigue , corrosion , paris' law , stress concentration , stress (linguistics) , metallurgy , hydrogen sulfide , cylinder , composite material , stress intensity factor , sulfide , fracture mechanics , sulfur , engineering , mathematics , mechanical engineering , linguistics , philosophy , geometry
In this paper, the fatigue crack growth rate of 15CrMo steel, a typical gas cylinder material, is studied under the condition of simulating the actual working condition of gas cylinder. The low-frequency corrosion fatigue tests with stress ratio of 0.1 and 0.5 are carried out in air and different concentrations of wet hydrogen sulfide environment. The relationships between d a /d N and Δ K are expressed by Paris equation. The results show that the crack growth rate in hydrogen sulfide environment with concentration of 200 ppm is 27 times higher that in air. The addition of corrosion environment greatly fasts the crack growth rate of 15CrMo steel. With the increase of H 2 S concentration, the crack growth rate increases exponentially. With the increase of stress ratio, the average stress increases, the crack closure effect decreases, the crack tip is fully opened, and the contact area with corrosion medium increases, which results in the increase of crack growth rate.