| 摘要 |
A creep-resistant steel is characterized by the following chemical composition (values in % by weight): 9.0 to 12.0 Cr, 0.1 to 0.5 Mn, 2.3 to 3 Ni, 1.5 to 2.0 Mo, 0.1 to 0.4 V, 0.01 to 0.06 Nb, 0.08 to 0.16 C, 0.02 to 0.08 N, 0.004 to 0.012 B, 0.001 to 2 Ta, 0.001 to 0.5 La, 0.0001 to 1 Pd, maximum 0.005 P, maximum 0.005 S, maximum 0.05 Si, maximum 0.005 Sn, the remainder iron and unavoidable impurities. This steel is distinguished, as compared with commercial steels, by a greatly improved creep behavior at temperatures of 550° C. and above. Moreover, it has an improved resistance to embrittlement during long-term aging and comparatively high toughness. The steel is advantageously used as a material for gas turbine rotors which are exposed to high inlet temperatures in order to increase the efficiency of the gas turbine, but is also used for steam turbines. |
