主催: 一般社団法人 日本機械学会
会議名: M&M2022 材料力学カンファレンス
開催日: 2022/09/26 - 2022/09/28
The effect of high temperature tension hold on fatigue crack growth in Inconel 718 is investigated. A single tension hold at maximum load was applied during cyclic loading at 650 °C, and the effect of load level and hold time are examined. In all experiments, a rapid acceleration of fatigue crack growth is observed immediately after tension hold. A retardation is observed after the initial acceleration at lower stress intensity factors, while only an acceleration occurs at higher intensity factors. These results are discussed by considering two competed mechanisms: grain boundary damage related to oxygen in front of the crack tip, and stress relaxation due to creep deformation.
