Microstructure and mechanical properties of as rolled high strength bainitic rail steels

Bainitic steels are emerging with the potential to replace eutectoid steels to achieve longer rail life. Bainitic steels of two compositions were made and processed into rails 13 m in length. The properties of these rails were evaluated in the as rolled slow cooled condition. The results from bainitic rail steels were compared with those for 880 MPa grade pearlitic rail steel. It was found that in the as rolled slow cooled condition rail properties such as fracture toughness, Charpy impact energy, and endurance limit were superior to those of 880 MPa grade pearlitic rail steel.