Modern martensitic steels for power industry

The article presents general characteristics of heat-resisting and creep-resisting steels intended for operation at increased temperature and having martensitic microstructure i.e. X10CrWMoVNb9-2 (T/P92), X11CrMoWVNb9-1-1 (E911) and X12CrCoWVNb12-2-2 (VM12-SHC). The weldability of the aforesaid steels is discussed on the basis of CCT diagrams of austenite transformation in welding conditions and the results of simulation tests aimed at determining the resistance of the steels to brittle and annealing cracking. The paper also contains information on test results related to mechanical (strength and plastic) properties of joints welded with various methods. The description of each of the steels under analysis has been supplemented with technological recommendations on welding and heat treatment of joints. The article is addressed to researchers who are interested in problems of heat- and high-temperature creep resisting constructional steels. Furthermore, the article is intended for designers, technologists and welding engineers engaged in constructional jobs in power industry.