The ratcheting behaviors and fatigue failure, as well as their interaction were investigated by uniaxial cyclic stressing
tests for 20 carbon steel at room temperature. The ratcheting strain and fatigue life of the material were measured in
varied loading levels. The effects of mean stress, stress amplitude and stress ratio on the ratcheting strain and final failure
life were discussed. The experimental results show that the ratcheting strain and fatigue life of the material greatly
depend on mean stress, stress amplitude and stress ratio in asymmetric stress cycling, and two kinds of failure modes (i.e.,
ratcheting failure due to large ratcheting strain and fatigue failure caused by the fatigue crack) occur respectively,
depending on the applied stress level in the tests.
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