腐食の局所性に注目した構造用鋼の腐食疲労き裂の発生および進展
1988 年 37 巻 415 号 p. 410-415
詳細
1988 年 37 巻 415 号 p. 410-415
Corrosion-fatigue crack initiation and growth behaviors of two high-strength steels (HT50 and HT80) and a rolled steel for general structure (SS41) were studied by taking a localized corrosion of specimen into account. The tests were carried out in the salt solutions having a concentration from 0wt percent (ion exchanged water) to 3wt percent. The following conclusions were drawn.
(1) The average diameter of corrosion pits was almost identical regardless of material and concentration of salt water. But, a wide separation of the corroded area (including many corrosion pits) and the lustrous uncorroded area occurred with an increase in concentration. It is considered that some corrosion pits were joined and led to the early initiation of surface cracks in salt water.
(2) The number of surface cracks was remarkably reduced with an increase in concentration of salt water. Localized corrosion along the surface cracks enhanced the growth in salt water. These phenomena influenced the fatigue properties in salt water.
