繰返し荷重下におけるステンレス鋼ならびにその溶接部の応力腐食割れに関する研究(第3報)
正弦波部分片振り引張荷重下における割れ特性
1973 年 42 巻 2 号 p. 100-105
詳細
1973 年 42 巻 2 号 p. 100-105
In this report we studied the effect of stress pulsation on resistance to stress corrosion cracking of AISI304 stainless steel in the boiling soultion of 42 % MgCl2 under partial pulsating sine wave load.
The experimental time to failure of stress corrosion cracking test was compared with the estimated time to failure calculated according to the static linear damage law, in which the time to failure was given as the accumulation of only static damage.
The in fluence of the variation of stress amplitude on the life is larger for the case in which the mean stress is low than for the case of the mean stress being high.
Moreover, when the stress amplitude is comparatively small (within about 4 kg/mm2), the estimated time to failure teq calculated according to the static linear damage law almost coincides with the experimental value and so the static linear damage law is applicable.
When the minimum stress σmin in the sine wave load is larger than the threshold stress of static stress corrosion cracking, the time to failure can be estimated by the time to failure of the static stress corrosion cracking test at the stress σmin and the stress variation ratio.
The threshold stress of streess corrosion cracking which is important from the viewpoint of design is also varied by the change of stress amplitude. When the threshold stress under the pulsating stress is expressed by the equivalent static stress, it almost coincides with the threshold stress under static stress.
