Out-of-phase thermomechanical fatigue crack propagation in a steam turbine steel — Modelling of crack closure
نویسندگان
چکیده
Understanding of crack growth behaviour is necessary to predict accurate fatigue lives. Out-of-phase thermomechanical propagation tests were performed on FB2 steel used in high-temperature steam turbine sections. Testing results showed closure where the compressive part cycle affected rate. Crack closing stress was observed be different, and had more influence rate, than opening stress. rate largely controlled by minimum temperature cycle, which agreed with an isothermal test. Finite element models stationary sharp cracks captured behaviour.
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ژورنال
عنوان ژورنال: International Journal of Fatigue
سال: 2021
ISSN: ['1879-3452', '0142-1123']
DOI: https://doi.org/10.1016/j.ijfatigue.2021.106251