heat treatment method of heated rails to obtain a microstructure that has improved mechanical properties

摘要

patent summary: "method and system for thermal rail treatments". The patent relates to a method of heat treatment of hot rails to obtain a desired microstructure having desired mechanical properties wherein the method comprises an active cooling phase wherein the rail is rapidly cooled from an austenitic temperature and subsequently cooled. smoothly to maintain a target transformation temperature between set values wherein the cooling treatment is performed by a plurality of cooling modules (12.n), wherein each cooling module comprises a plurality of means that spray a cooling medium. where the process is characterized in that during the active cooling phase each cooling medium is triggered to control the rail cooling rate so that the amount of austenite transformed within the rail is not less than 50 % on rail surface and not less than 20% on rail billet core.