Steam turbine rotor for high temperature

摘要

The present invention is directed to a steam turbine rotor which comprises an iron base alloy containing 0.05 to 0.2 wt % of carbon, 0.1 wt % or less of silicon, 0.05 to 1.5 wt % of manganese, more than 8.0 wt % to less than 13 wt % of chromium, less than 1.5 wt % of nickel, 0.1 to 0.3 wt % of vanadium, 0.01 to 0.1 wt % of niobium, 0.01 to 0.1 wt % of nitrogen, 0.02 wt % or less of aluminum, less than 0.50 wt % of molybdenum and 0.9 to 3.0 wt % of tungsten; contents of molybdenum Mo and tungsten W satisfying the following formulae 0.75