Influence of rail chemical composition
Electric flash butt welding of railways rails

The influence of chemical composition on the TRC (continuous cooling transformation) curve was described in the article "Rails de chemins de fer. Aspects métallurgiques" [M 3 070] the influence of chemical composition on the TRC (continuous cooling transformation) curve, which defines the cooling rate to be adopted in order to obtain a pearlitic structure without any trace of martensite.

Some high-alloy grades may require heavy-duty postheating after welding to reduce the cooling rate, which has the disadvantage of enlarging the heat-affected zone (HAZ).