Development of mechanical fuse parts for car air conditioner

There has been a growing need in recent years for a car air-conditioner having a variable-displacement compressor. As for such a type of compressor, mechanical breaker for protecting the engine belt is required. Mechanical breaker can be realized by developing a material having high fatigue limit ratio (fatigue strength/tensile strength) and improving the stability of breaking load. To solve these problems, we developed the new Fe-Cu-C material and the process by which mechanical properties of the new material are very much stabilized. In this paper, we summarize the background and the technical contents of this development.