Zirconium is an important material in nuclear industry because of its low neutron absorption cross section, excellent corrosion resistance and machining properties. Most of the atomic zirconium produced in the major zirconium producing countries is used in atomic reactors. Apart from nuclear-powered submarines and aircraft carriers, 440 civilian nuclear power plants have been built and in operation around the world. The world zirconium production capacity is about 7000t/a, and the amount used in the nuclear industry is about 3000t per year. The industrial grade zirconium containing hafnium is used in the metallurgy, chemical, machinery and weapons industries, with an annual consumption of about 2000t. Hafnium metal can be used as the control rod of nuclear reactor due to its high absorption cross section. It can also be made into alloys for spacecraft and other high temperature resistant parts.
Zirconium is an active metal with great affinity to oxygen. The excellent corrosion resistance of oxide film determines that zirconium can be used in multiple corrosion environments.
1. Corrosion rates of industrial pure zirconium at all boiling concentrations of hydrochloric acid are less than 0.025mm/a.
Zirconium has excellent corrosion resistance in sulfuric acid of less than 70%. In addition, zirconium plays an irreplaceable role in sulfuric acid environment because stainless steel and nickel alloy cannot be used in the sulfuric acid range below high temperature, 20% sulfuric acid and 40-60% boiling temperature.
3. Zirconium has good corrosion resistance under 200℃ and no more than 90% nitric acid. However, the sensitivity of zirconium to stress corrosion cracking in nitric acid should be noted.
Zirconium is resistant to corrosion at all concentrations, even in boiling aqueous caustic solutions. Corrosion resistance exceeds tantalum, niobium and titanium.
At the same time, zirconium is not suitable in some environments, such as in fluoride ion medium zirconium corrosion resistance. Therefore, it is necessary to determine whether the zirconium material is suitable for working conditions
Zirconium plate application field: oil tank coil, shell tube heat exchanger, thermal-siphon, evaporator, nozzle heater and manmade filament capsule, shell and tube type heat exchanger, tube type heat exchanger, tube type preheater, chemical equipment, reactor coil, etc.
