Current Studies on Ultra-long-life Fatigue Properties for Metallic Materials Mainly Focusing to Bearing Steels: Fundamental Fatigue Data required to EcoDesign of Mechanical Structures

If we use every mechanical structure for a long period two times of the conventional design life, we can realize saving the resources into one half and environmental loads to the globe can be also reduced into one half. Thus, the long life design of the mechanical structures gives us a typical technology to facilitate the application of "EcoDesign" into the industrial societies. From this point of view, the fatigue behavior of high-strength steels in the ultra-long-life regime was clarified as the fundamental design data.