Room temperature mechanical properties and high temperature oxidation resistance of a high Cr containing Nb–Si based alloy

Abstract A high Cr containing Nb–Si based alloy (Nb–12Si–24Ti–10Cr–2Al–2Hf) was prepared by non-equilibrium rapid directional solidification, and then was heat treated at 1400 °C for 10 h. The microstructure was greatly improved by these processes. Big block-like Nb 5 Si 3 was avoided and vermicular one as a strengthening phase uniformly distributed in the toughening Nb SS matrix. Exciting fracture toughness (17.9 MPa m 1/2 ) and tensile strength (771 MPa) were achieved for this high Cr containing Nb–Si based alloy. Oxidation behaviors of this alloy at 1200 °C and 1250 °C were also studied.