Zirconium is a kind of active metal with great affinity with oxygen. The excellent corrosion resistance of the oxide film determines that it is suitable for multiple corrosion environments.
I. the corrosion rate of industrial pure zirconium in all boiling concentrations of hydrochloric acid is less than 0.025mm/a.
Zirconium has excellent corrosion resistance in sulphuric acid less than 70%. In addition, because stainless steel and nickel alloy cannot be used at high temperature, 20% sulfuric acid and 40-60% boiling temperature below the range of sulfuric acid, zirconium in sulfuric acid environment has irreplaceable role.
Three, below 200℃, no more than 90% of nitric acid, zirconium has a good corrosion resistance. However, stress corrosion cracking sensitivity of zirconium in nitric acid should be noted.
Zirconium is resistant to corrosion at all concentrations even in boiling caustic solutions. Corrosion resistance than tantalum, niobium, titanium.
Zirconium alloy is mainly used as the cladding material of nuclear reactor fuel element and other reactor internal components. The main research results and problems about water corrosion of zirconium alloys are reviewed. The existing theories and challenges are summarized. Great progress has been made in the study of chemical composition, microstructure and irradiation effects on corrosion resistance of zirconium alloys in the 1980s. In recent years, the research work mainly focused on exploring the corrosion mechanism, selecting the best alloy composition and controlling the microstructure, so as to meet the higher requirements for zirconium alloy after increasing fuel consumption and reducing nuclear power cost.
