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Niobium alloy is an alloy based on niobium and added with other elements. Niobium is a refractory metal with a melting point of 2467℃ and high specific strength in the temperature range of 1093 to 1427℃. Compared with tungsten alloys and molybdenum alloys, niobium alloys have good plasticity and excellent processing and welding properties, so they can be made into thin plates and parts with complex shapes, and can be used as thermal protection and structural materials in the aerospace and aviation industries.

Commercial niobium alloys are poor in strength and super ductility, and 70% of niobium alloys require cold working before annealing. As a result, niobium alloys with complex structures and lower densities can be easily produced. Generally people prefer niobium alloys to other refractory metals such as molybdenum, tantalum, and tungsten. In the 1960s, a number of high-temperature niobium alloys were developed, primarily for nuclear weapons and aerospace requirements; however, further development has been limited since the early 1970s. Today, niobium alloys are also used in smart human devices. Transportation satellites and a wide range of high-temperature components, however, there will be wider use of these alloys in other applications due to their susceptibility to oxidation at high temperatures and long periods of operation.

Although these elements improve the strength and hardness, toughness, sensitivity and texture of the alloy, which are equal to or better than pure niobium, in most cases, alloying niobium with tantalum, titanium, and vanadium must be rapid and the formation process is complicated. All other alloying elements significantly reduce toughness, sensitivity and texture. In general, niobium alloys are more tolerant of pick-up impurities than other opposite metals (e.g. Zr, Ti), since these impurities can greatly reduce the stretch, mainly at the grain edges. For example, the mechanical properties of these alloys become significantly worse when copper is incorporated.

In order to improve the oxidation resistance at high temperatures, niobium alloys are widely wrapped with special processes, such as silicon. Most niobium alloys are produced by electron beam, plasma and vacuum arc melting with appropriate additive elements. For large ingots, two smelting operations are required to produce suitable ingots with appropriate ingredients. Today, most common alloy additives are titanium, zinc, tungsten, tantalum and hafnium, all of which are stably incorporated during the melting process.

Another promising method for producing niobium alloys is electrodeposition from molten salts, such as deposition from the Kel-KF-K2ZrF6-K2NbF7 system.

Niobium-based alloys can also be prepared by powder metallurgy. Several methods can be used to prepare niobium alloy powders, including gas-atomization, quenching, mechanical fusion, high-temperature diffusion or hydride dehydrogenation processes. However, when using these methods, oxidation and the introduction of impurities are difficult to avoid and expensive.