Some aspects of creep behaviour of 2.25 Cr-1Mo Steel

Creep and stress rupture properties of 2.25Cr-1Mo steel having diffrent initial microstructure have been evaluated. Bainitic structure has been found to give maximum rupture strength where as ferrite carbide structure provides maximum rupture ductility. Ferrite-bainite structure provides an optimum combination of srength and ductility.

Commercial grades of steels conforming to the specification may have minor variations in chemical composition. It has been shown that these variations can significantly alter the initial microstructure and thus influence stress rupture properties. Section size of the product may also have similar effects on long term rupture propeties.