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Abstract: High temperature low-cycle fatigue test with hold time
ranging from 10 s to 60 s are performed on 30Cr1Mo1V under a fully
reversed axial total strain control mode at 540 ℃and 565 ℃. The strain
amplitudes are 0.6% ~1.2%, the waveforms are symmetrical trapezium. The
relaxation phenomena and the strain-life laws are investigated. Several
commonly used fatigue-creep life prediction methods are chosen to
analyze the experimental data. The scatter band factor and standard
deviation are used to test validity of these life prediction methods.
The results show that the ratios of the first and the third stage are
increasing whereas the ratio of the second stage is decreasing with the
increasing strain. The relaxation ratios are almost the same during
tensile hold time and compress hold time with stress for reference. The
linear damage summation method and the strain range partitioning method
have higher precision, whereas the strain energy partitioning method and
the modified frequency Manson-Coffin method are weaker in
life-prediction. In addition, life prediction formula of this material
are presented of these life-prediction modes.
Key words: 30Cr1Mo1V steel Creep Fatigue Strain-controlled
Low-cycle fatigue
CLC No: TH140.1
华北电力大学博士学位教师科研基金资助项目(2004-4).
Received 20040318, received in revised form 20040819
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