The invention relates to a directional-freezing heat-proof
corrosion-resistant
nickel base cast
superalloy with low cost and excellent performance. The cast
superalloy has the
chemical composition range by weight percentage as follows: C is 0.04 to 0.09; Cr is 14.5 to 15.3; Co is 9.0 to 9.9; W is 4.7 to 5.9; Mo is 1.6 to 2.3; Al is 2.8 to 3.3; Ti is 4.2 to 5.0; Hf is 0.3 to 0.6; Ta is 0.3 to 1.5; B is 0.06 to 0.10; Y (adding quantity) is 0.015; Mn is less than or equals to 0.2; Si is less than or equals to 0.2; P is less than or equals to 0.008; S is less than or equals to 0.008; Fe is less than or equals to 0.5; the other weight percentage is composed of Ni. A
vacuum induction furnace is adopted to smelt master
alloy, and the directional-freezing is performed in a liquid-
metal-cooled (LMC) furnace to prepare columnar grain
alloy; the vacuum degree of a directional furnace is less than or equals to 5*10<-4>mmHg, the
casting temperature ranges from 1480 to 1570 DEG C, the drawing velocity is 3 to 15mm / min, the
temperature gradient is 95 to 145 DEG C / cm, and the temperature of melting
tin ranges from 250 to 350 DEG C. The invention provides the heat-proof
corrosion-resistant
superalloy, which contains Ta, does not contain alloying elements that are Re (with low cost), Nb, Zr and Ce, and has a stable
microstructure. Compared with cheC88 Y-BN, the tensile-strength (using
Delta (b) and
Delta0.2 to represent) is increased more than 30 percent, the
plasticity is improved obviously, the lasting temperature is risen by 30 DEG C under the same stress condition, and the cast superalloy is applied to manufacture
turbine blades of a
combustion turbine which is used under 930 DEG C.