The concrete method is as follows: when the rail or the wheel of the eutectoid component is heated by the high-frequency induction or the flame is heated to 850~900 DEG C, the quenching process is cooled by compressed air or spray. The cooling speed of quench water quenching than the general low, thus obtained the fine pearlite.
Quenched rails are hardened when rails are finished, so the advantage is to increase the hardness of the rails
. In the past, the heat treatment of the rail head was made by high frequency induction heating or flame heating to 850~900 degree Celsius, and then quenched at 600~650 C for tempering at high temperature to obtain the structure of tempered bainite.
Quenched rail is under speed quenching. It has on-line residual heat quenching and off-line heating quenching. The cooling mode is usually jet blast or jet wind and spray cooling, and its microstructure is pearlite. Hardness is HRC36~42.
