オーステナイト系ステンレス鋼SUS 304の純水中における高サイクル熱疲労き裂発生挙動

概要

論文の詳細を見る
Temperature fluctuations in power plants may cause thermal fatigue in structures, In order to maintain integrity of structures, the thermal fatigue life has to be evaluated including high cycle fatigue conditions on which few investigation has been performed so far. In the last study, a facility for high cycle thermal fatigue testing in pure water was developed. To clarify the high cycle thermal fatigue crack initiation behavior of type 304 stainless steel in pure water environment, high cycle thermal fatigue tests were conducted using the developed facility for various water temperature fluctuation frequency and water temperature fluctuation range in this study. The thermal stresses induced on the labyrinth corner of the cylindrical specimen were analyzed by FEM. The heat transfer coefficient experimentally evaluated using the thermal fatigue testing facility was applied to the analysis. Thermal fatigue cracks were initiated at the corner of the labyrinth for the stress amplitude and over 294 MPa. On the other hand, the mechanical fatigue crack initiation lives were derived from the mechanical fatigue of type 304 stainless steel. It was demonstrated that the number of cycles to thermal fatigue crack initiation agreed with that of the mechanical fatigue crack initiation when the fictitious stress amplitudes were identical.
社団法人日本機械学会の論文
1999-11-25