Niobium base alloy, simple process, high metal utilization rate. In particular, the direct hydrogenation of niobium ingots can reduce the pollution of impurities such as oxygen, iron and silicon. Before hydrogenation, niobium ingots only need to be properly pickled, and the process is particularly simple. From niobium ingots to electrodes, the utilization rate of niobium can reach more than 80%. Pressing directly with hydrogenated powder is beneficial to powder preservation and reduce inspirations.
The niobium base alloy produced by the manufacturing process has uniform composition and can basically eliminate the non-frit of high melting point metal. For 30 kg of Nb-50Ti alloy melted by electric arc furnace, the fluctuation range of titanium is 1-1.5 % by weight; The fluctuation range of titanium in the alloy ingot smelted twice by electric arc furnace is < 1 % by weight. The microcomponent analysis of the alloy shows that the fluctuation range of titanium is 2.5-4.6 % by weight, and the alloy fully meets the requirements of the production of composite superconducting wires, especially for the production of composite superconducting wires with a core diameter of less than 10 microns and the composite superconducting wires for magnets with high magnetic field uniformity. The electrode made by the process is very convenient when loading the furnace pair; Electrode in the melting process of small gas discharge, easy to maintain the melting vacuum, stable arc, less metal splash.
With the prepared niobium hydride powder and the particle size < 20 target market sales of dielectric titanium powder, according to the proportion of Nb49 weight %, press into a diameter of 40-45×180 mm electrode, the pressure is 2 tons/cm2.
The pressed electrode is sintered in order to remove hydrogen and increase the strength of the powder electrode, and the niobium-titanium portion is solid dissolved. Pre-vacuum 8×10-2Pa during sintering, and then heat up to remove hydrogen first, dehydrogen from about 300 ℃, to 650-700 ℃ heat preservation until the vacuum degree returns to 8×10-2Pa. Continue to heat up to 1400 ℃, hold for 2 hours for high temperature sintering. X-ray phase analysis showed that solid solution was formed between niobium-titanium.
The sintered electrode was smelted twice by electric arc furnace to obtain 20 kg alloy ingot. The fluctuation range of titanium is ±0.5 % by weight. Microanalysis shows that titanium fluctuates in the range of 2.5-4.6 % by weight. From niobium ingot to alloy ingot, the utilization rate of niobium is more than 80%. No niobium non-frit was found on the cross section and profile of the alloy ingot, and the oxygen content of the alloy was less than 1000ppm.
