鋼の疲労過程における履歴曲線の発生機構の転位-炭素原子相互作用モデルによる考察

抄録

The problem of the initiation of hysteresis loop of low carbon steels was dealt mainly from the theoretical view point under the condition that the material was subjected to the repeated stress in the range comparable to its long life fatigue. The experimental observations of hysteresis loop were first made on three kinds of low carbon steel with different concentrations of solute atoms. The theoretical calculations were, then, carried out by means of a theoretical model based on the interaction between carbon atoms and dislocations, and the results were compared with the experimental results. The basic concept in establishing the model is that the diffusion of solute carbon atoms is far more rapid through the pipe diffusion process along the bowed out dislocation lines than through the volume diffusion process and the rapid unpinning of dislocation strings takes place, leading to the observable growth of hysteresis loop in each stress cycle even at room temperature.