311 球状黒鉛鋳鉄の超高サイクル疲労に関する組織と負荷形式の影響(OS1-2 高強度材の超高サイクル疲労(2))(OS1 高強度材・表面改質材の疲労と破壊)  [in Japanese] 311 Effects of microstructures and loading form to long-term fatigue properties of ferrite-base spheroidal graphite cast iron  [in Japanese]

In order to apply the ultra-sonic fatigue test as an accelerated method for the practical use, fatigue test have been performed on ferrite-base spherical graphite cast iron. Materials used have various graphite diameters and the tensile strengths. The testing method includes the axis-direction fatigue, rotating-bending and ultra-sonic fatigue tests. In the present study, after various parameters have been considered, a equation is proposed for prediction the rotating-bending or axis-direction fatigue limits from the ultra-sonic fatigue testing results.