Development of Compacted Vermicular Graphite Cast Iron Brake Disc for Railway Rolling Stock

Flake graphite cast iron has been used for brake discs of railway rolling stock. In accordance with increasing speed of railway cars, higher strength has been required for disc brakes. In the present investigation, compacted vermicular graphite cast iron brake discs with higher strength were developed. A paper reports on procedure in the development and results of various tests including friction, fatigue, and high temperature strength as well as tensile strength. A braking test was conducted with using a braking tester. At present, CV (Compacted Vermicular) graphite iron brake discs are being used for limited express and production amounted to more than 500 tons by 1998 fiscal year.