Effect of Scale Factor on the Structure and Mechanical Properties of Nickel β-Alloy Produced by Centrifugal SHS Casting

Abstract—The chemical and phase compositions, structure and mechanical properties of an alloy based on the NiAl—Cr—Co system (base–2.5Mo–1.5Re–1.5Ta–0.2Ti) obtained by centrifugal SHS casting in a pilot industrial plant have been studied. The results of the study were analyzed in comparison with similar parameters for an alloy of the same composition, but synthesized in a laboratory SHS plant and having a smaller mass of 0.8 ± 0.1 kg as compared to the mass of a large-sized ingot of 4.7 ± 0.1 kg. The large-sized ingot with chemical and phase compositions uniform by volume is reported to have been produced, its metal demonstrating similar kinetics and heat resistance at 1150°C (30 h) at different distances from the center. It was found that the heat resistance of the alloy decreased with ingot mass increasing from 55 ± 3 g/m2 for the laboratory ingot to 19 ± 3 g/m2 for the large ingot. The strength properties of the metal of the large ingot during compression testing were $$\sigma _{{\text{u}}}^{{\text{c}}}$$ = 1662 ± 10 MPa, $$\sigma _{{0.2}}^{{\text{c}}}$$ = 1531 ± 25 MPa and during tensile testing σu = 293 ± 10 MPa, σ0.2 = 236 ± 5 MPa, which was practically no different from the properties of the laboratory ingot. The mechanical properties of NiA–Cr–Co-based alloys of various alloying systems synthesized by the SHS method with subsequent use of special metallurgy methods are also given.