High purity niobium
Technology of receiving high purity niobium (99.9%) to produce superconducting resonators is developed.
High purity niobium production technology includes serial electrolytic refining and multiple electron-beam remelting in high oil-free vacuum (Р<5Т0" mm Hg).
High purity niobium used in superconducting resonators production is characterized by relative residual resistance size (RRR)>500, which is provided due to ultralow content of refractory metal impurities (W, Та, Mo <100 ррt), as well as due to volatile impurities (О, С, N < 20ррt).
Rolled high purity niobium is used in enterprises of electronic industry, and in scientific centers studying problems of high-energy physics and superconductivity.
High purity niobium production volume is 500 kg per year.