熱応力の計算例と疲労寿命算出の問題点

抄録

The piston crown of a diesel engine is subjected to both thermal and mechanical stresses. The thermal stress arises from temperature gradients in the piston crown, and the mechanical stress to gas pressure. These stresses are superposed each other.
The fatigues under superposed wave stresses have been studied considerably in the past and several methods for fatigue life prediction under such stresses have been proposed.
In this paper, the fatigue behaviors under superposed wave stresses are investigated and a new method to predict the fatigue life is proposed. An example of the prediction on the piston crown of a diesel engine is also presented.