Preparation method for oxidation resisting self-healing Cr/NiCr coatings on niobium-based surface

The invention discloses a preparation method for oxidation resisting self-healing Cr/NiCr coatings on a niobium-based surface. The preparation method comprises the following steps that (1) after a niobium matrix or a niobium alloy matrix is preprocessed, ion bombardment cleaning operation is conducted on the niobium-based metal surface by using Cr ions generated by a Cr target; (2) a Cr transition layer is deposited on the niobium-based metal surface by using the Cr ions generated by the electric arc Cr target; (3) a NiCr composite layer is deposited on the surface of the Cr transition layer by using Ni ions and the Cr ions generated by an electric arc Ni target and the electric arc Cr target correspondingly; (4) the operations of surface bombardment and sputtering are conducted on a NiCr middle composite layer by using the Cr ions generated by the electric arc Cr target; and (5) after the step (3) and step (4) are repeated at least three times, compact Cr/NiCr multi-layered composite coatings not less than 1