Niobium alloy is an alloy formed by adding several elements to niobium as the base, and it has the following characteristics:
Good mechanical properties: The strength of niobium alloys is usually higher than that of pure niobium. For instance, the room-temperature yield strength of Nb-1Zr alloy can be increased to over 300MPa. Moreover, through reasonable composition design and processing technology, it can ensure a certain degree of toughness while making its toughness comparable to or even better than that of pure niobium. Meanwhile, the addition of alloying elements alters the crystal structure of niobium, increasing the resistance to dislocation movement, thereby enhancing its hardness and making it perform outstandingly in terms of wear resistance and scratch resistance.
Excellent high-temperature resistance: Niobium alloys can withstand extreme temperatures as high as 1700 degrees Celsius or even higher. For instance, Nb-Si series alloys can still maintain a tensile strength of over 500MPa at 1200 degrees Celsius, which is much higher than that of nickel-based superalloys. They can be used to manufacture high-temperature components such as turbine blades and combustion chambers for aero engines.
Strong corrosion resistance: Niobium alloys exhibit excellent corrosion resistance to inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid, as well as organic acids like acetic acid and citric acid at room temperature. They also remain stable in polar organic solvents such as ethanol and acetone. For instance, the Nb-1Zr alloy valve can withstand the long-term erosion of acidic media containing Cl⁻, and the Zr-2.5Nb alloy still maintains excellent corrosion resistance in high-temperature and high-pressure water at 300-400℃.
Possessing superconducting properties: Some niobium alloys have excellent superconductivity. For instance, Nb₃Sn and NbTi are traditional low-temperature superconducting materials. The critical magnetic field of Nb3Sn can reach 23T, while NbTi, although having a lower critical field, has good plasticity and can be formed through cold working. Both are widely used in MRI magnets and particle accelerators.
