A zirconium alloy is a colored alloy formed by adding z […]
A zirconium alloy is a colored alloy formed by adding zirconium as a matrix to other elements. The main alloying elements are tin, antimony, iron, and the like. Zirconium alloy has good corrosion resistance, moderate mechanical properties, low atomic thermal neutron absorption cross section in high temperature and high pressure water and steam at 300-400 °C, good compatibility with nuclear fuel, and is mostly used as water-cooled nuclear reactor. Core structure material. In addition, zirconium has excellent corrosion resistance to various acids, bases and salts, and has strong affinity with gases such as oxygen and nitrogen. Therefore, zirconium alloy is also used in the manufacture of corrosion-resistant parts and pharmaceutical mechanical parts in the electric vacuum and bulb industry. It is widely used as a non-evaporable getter.
Zirconium alloys produced on an industrial scale are of the zirconium-tin and zirconium-based systems. The former alloy grades are Zr-2 and Zr-4, and the latter is typically Zr-2.5Nb. In the zirca-tin alloy, the alloying elements tin, iron, chromium, and nickel improve the strength, corrosion resistance, and thermal conductivity of the corrosion-resistant film, and reduce the sensitivity of the surface state to corrosion. Usually Zr-2 alloy is used for boiling water reactor and Zr-4 alloy is used for pressurized water reactor. In the zirconium-lanthanum alloy, when the amount of niobium added reaches the solid solution limit of the crystal structure of zirconium at the use temperature, the corrosion resistance of the alloy is the best. The zirconium alloy has a homomorphic transformation, the crystal structure at high temperature is body-centered cubic, and the dense-packed hexagonal at low temperature. The zirconium alloy has good plasticity and can be made into pipes, plates, rods and wires by plastic processing; its weldability is also good, and it can be used for welding processing.