20th International Forgemasters Meeting - IFM 2017

In terms of increasing power demand in the world and a problem of global warming, high-efficient thermal power plant has been desired. A rise in steam temperature is an effective way for improvement of power generation efficiency, therefore a number of high temperature materials and components for USC/A-USC pressure turbine have been developed for many years. JSW began manufacturing conventional 12Cr rotors containing Ta or Nb in 1971, and then has developed advanced 12Cr steels and new 12Cr steels containing Co and B for turbine rotors in collaboration with turbine manufacturers in 1980's and 1990's respectively. These results greatly contributed to the increase in capacity and efficiency of fossil power generation, related to reduce the emission of greenhouse gases. Aiming at further high efficiency, we have developed high Cr ferritic steels for USC turbine rotors which are available at 630 degree C and manufacturing processes for Ni based super alloys for A-USC turbine rotors since 2000. Above-mentioned history of the development and the manufacturing of the high-intermediate pressure turbine rotors in JSW will be reviewed with a focus on 12Cr steels.