The method of determining niobium content in aviation material Ti45Nb titanium alloy is to dissolve insoluble test material with mixed acid of hydrochloric acid, nitric acid and hydrofluoric acid. In hydrofluoric acid medium, titanium and aluminum ions are formed stable complex by hydrofluoric acid, niobium and tetraphenylarsenic chloride hydrochloride are completely precipitated, and trace magnesium ions are soluble precipitated. Tartaric acid is used to prevent the precipitation of hydrated oxides of high-priced metal ions, after filtration, the magnesium precipitation is washed and dissolved, and finally the precipitation is dried, ash, and burned into niobium pentaoxide, and the niobium content in the alloy is calculated by weighing and calculating. The method of the invention has an alloy material with a mass fraction of 40.0% ~ 50.0% that can determine the niobium content. It has the advantages of simple operation, high accuracy, small error and good stability.

The preparation method of wide plate width barrier layer Niobium Sheet for superconducting wire includes: first, the Niobium Plate is rolled along a fire after reversing rolling, and then the niobium plate is obtained by grinding, sanding, pickling, shearing and vacuum annealing; Second, the niobium plate with tension rolling, and then in turn for grinding, sanding, pickling, shearing and vacuum annealing heat treatment to get wide plate width barrier layer niobium sheet

Method of producing superconducting niobium pipe. It is characterized by the following steps: taking cylindrical high-purity niobium ingots to drill holes to get hollow ingots, extruding the hollow ingots at room temperature to get tube billets, and then rolling the tube billets to get finished niobium tube.