| 摘要 |
<p>(1) A steam turbine rotor material for high-temperature use which comprises 0.05 to 0.13 wt.% carbon, 0.01 to 0.1 wt.% silicon, 0,01 to 1 wt.% manganese, 9.5 to 11 wt.% chromium, 0.1 to 0.8 wt.% nickel, 0.1 to 0.3 wt.% vanadium, 0.01 to 0.2 wt.% niobium and tantalum, 0.01 to 0.1 wt.% nitrogen, 0.01 to 0.5 wt.% molybdenum, 0.9 to 3.5 wt.% tungsten, 0.1 to 4 wt.% cobalt, 0.01 to 0.2 wt.% hafnium, inevitable impurities, and iron. (2) A steam turbine rotor material for high-temperature use having the same composition as the material (1) except that nickel is not contained. (3) A steam turbine rotor material for high-temperature use having the same composition as the material (1) or (2) except that it further contains 0.001 to 0.01 wt.% boron. (4) A steam turbine rotor material for high-temperature use having the same composition as the material (1), (2), or (3) except that is further contains 0.005 to 0.5 wt.% neodymium in place of part or the whole of the hafnium and/or part of the iron</p> |
