熱処理による鋼球の残留応力について

鋼球の残留応力について(第1報)

抄録

The fatigue of the steel balls is influenced by the residual stresses. The purpose of this paper is to research the behavior of the residual stresses in the steel balls heat-treated at various conditions. The stresses are measured by X-ray diffraction.
The results obtained are summarized as follows:
1.The residual stresses do not always increase, even though the quenching temperature is raised. As a result there exists a quenching temperature in which the residual stresses are at the maximum.
2. As the tempering temperature is raised, the residual stresses after quenching decease.
3. The residual stresses change little by the tempering time.
4. The residual stresses in the steel balls quenched in oil are smaller than those quen-ched in water.
5. Subzero treatment has no influence upon the residual stresses.
All measured residual stresses in the steel balls are found to be compressive stresses which are useful for the fatigue life.