Elastic Modulus Variation of 10CrNiMo Structural Steel in the Process of Low Cycle Fatigue

Elastic modulus variation of 10 CrNiMo structural steel in the process of low cycle fatigue was researched by smooth and rounded cross-section specimens, controlled by six series of different axial strain amplitudes ranging from 0.3% to 1.0%. The results displayed that elastic modulus under the stable cycles is changeable and decreases by power-function with a negative exponent with the strain amplitude increasing, and the elastic modulus has a deviation of over 15% between the biggest strainamplitude and the smallest one; controlled by a certain strain amplitude, elastic modulus drops slightly with the increasing cycles and decreases quickly at the failure point during stable cycles. Analysis shows that the phenomena are relative to different strain amplitudes resulting in different amount of fatigue damages and intrinsically durative resistance against fatigue of the tested materials under the control of constant strain amplitude.