Nickel-base casting superalloy and cast component for steam turbine using the same

摘要

A Ni-base casting superalloy containing, in mass%, C: 0.05 to 0.2, Si: 0.01 to 1, Mn: 0.01 to 1, Co: 5 to 20, Fe: 10 or less, Cr: 15 to 25, and one kind or two kinds or more of Mo, W, and Re, with Mo + (W + Re)/2: 8 to 25, the balance being Ni and unavoidable impurities. Optionally Ti, Al, Nb, ta, B or Zr are contained.