Effects of Alloying Elements and Process on the Thermal Stability of AustemperedDuctile Iron

摘要

KYMENITE, i.e. Finnish trademark for Austempered Ductile Iron, has been used onan industrial scale in Finland on a rapidly increasing basis since 1973, after it was discovered as a result of pioneering research work at Hogfors Foundry in Finland. The first applications of this material were heavily loaded gears. The special features that make KYMENITE a suitable material for demanding applications are based on its unique microstructure, which consists of acicular ferrite and high carbon stabilized austenite. Of great importance is also the stability of the austenite, depending on the alloying contents, austenitizing and austempering processes when focussing attention on the dimensional accuracy of ADI components under the service conditions at the elevated temperatures.