船体用高張力鋼板(YP40鋼)の腐食疲労特性

抄録

This paper describes corrosion fatigue properties of KA40 which is high tensile steel for a ship hull approved by Class NK. The structure of a ship hull is in a severe corrosive environment and subjected to cyclic loads due to waves. It is important to grasp the corrosion fatigue properties of materials for the structure of a ship hull. However, there are few reports of corrosion fatigue test results for hull structural materials. Therefore, further data accumulation is required to understand the corrosion fatigue properties of hull structure composed of materials with various mechanical properties. In this study, fatigue tests and fatigue crack propagation tests by using specimens for KA40 were carried out both in air and in synthetic seawater. Furthermore, in comparison of the results of KA40 with the results of KA32, the relationship between the difference in mechanical properties and the corrosion fatigue properties of each material is discussed.