Casting method of Niobium-titanium superconducting alloy
(1) True blank arc furnace melting casting with powder as raw material:Niobium and titanium powder are used as raw materials, mixed according to the appropriate proportion, molded into electrodes, after high temperature curing, welding by the true blank arc furnace melting casting twice or more, the niobium titanium alloy ingot is prepared.
(2) True blank consumable arc furnace melting casting method with strip or rod electrode preparation:Niobium and titanium raw materials are melted and processed respectively to produce strip or rod. After they are prepared into electrodes, niobium titanium alloy ingots are fused and cast twice or more in vacuum consumable arc furnace.
(3) Combined melting and casting method of vacuum electron beam furnace and vacuum consumable arc furnace with strip or rod electrode:In the same method, niobium and titanium are made into strips or rods respectively, and the electrodes are prepared. The niobium titanium alloy ingot is obtained by melting and casting in vacuum electron beam furnace and true blank consumable arc furnace.
(4) Vacuum electron beam furnace melting casting method with strip or rod electrode preparation:Niobium and titanium are made into strip or rod respectively, which are prepared as electrodes, and are fused and cast twice or more in vacuum electron beam furnace to obtain niobium titanium alloy ingot.
(5) with high quality sponge titanium and niobium rods prepared electrode for the purification of electron beam is blank electricity arc furnace with true shell furnace smelting method, by the high quality sponge titanium compressed into rods, with the vacuum electron beam furnace melting mixture electrode, purification of niobium rods in true blank electricity arc furnace and shell furnace inside two kinds of furnace type, joint into niobium titanium alloy ingot casting.
The above niobium-titanium superconducting alloy casting method using niobium-titanium powder as raw materials has some advantages in the preparation of niobium-titanium alloy with high uniformity, but it is easy to cause more gap impurities and complicated process.
The niobium-titanium superconducting alloy ingot fused by vacuum electron beam furnace with niobium, titanium strip or rod as electrode can get excellent plastic alloy with few impurities, especially with few interstitial impurities, but the content of titanium in the alloy component niobium-N fluctuates widely.
The content of titanium in different parts of niobium alloy ingot is fluctuated in ± 1.5%. However, the fluctuation range of vacuum electron beam furnace casting is ± 3% or slightly more.
The fifth kind of niobium alloy melting casting method is a unique method adopted by the northwest Institute of nonferrous Metals in China.
The process is simple, and the niobium alloy ingot with high uniformity can be obtained, and the niobium alloy with low impurity content can be prepared.