What does Zircaloy mean?
Definition of zircaloy : any of several zirconium alloys notable for corrosion resistance and stability over a wide range of radiation and temperature exposures.
Why Zr is used in nuclear reactor?
Zirconium is the metal of choice in this application because it absorbs relatively few of the neutrons produced in a fission reaction and because the metal is highly resistant to both heat and chemical corrosion.
What can be a problem with zirconium casings a nuclear reactor?
One disadvantage of metallic zirconium is that in the case of a loss-of-coolant accident in a nuclear reactor. Zirconium cladding rapidly reacts with water steam above 1,500 K (1,230 °C). Oxidation of zirconium by water is accompanied by release of hydrogen gas.
What is zirconium used for?
Zirconium(IV) oxide is used in ultra-strong ceramics. It is used to make crucibles that will withstand heat-shock, furnace linings, foundry bricks, abrasives and by the glass and ceramics industries. It is so strong that even scissors and knives can be made from it.
Is zirconium used in stainless steel?
Stainless steel–zirconium (SS–Zr) alloys have been developed for the consolidation and disposal of waste stainless steel, zirconium, and noble metal fission products such as Nb, Mo, Tc, Ru, Pd, and Ag recovered from spent nuclear fuel assemblies.
How does zirconium react with water?
Zirconium does not react with water under normal conditions. Zirconium is coated with an oxide layer that usually renders it inactive. However zirconium does burn in air if provoked to form zirconium(IV) oxide, ZrO2.
What is the density of zirconium?
| P H Y S I C A L D A T A | |
| Group 4 transition metal Density / kg m-3 : 6506 [293 K]; 5800 [liquid at m.p.] | Melting point / K : 2125 Boiling point / K : 4650 |
| D I S C O V E R Y | |
| Zirconium was discovered in 1789 by M.H. Klaproth at University of Berlin, Germany. First isolated in 1824 by J.J. Berzelius at Stockholm, Sweden. |
What is the hardness of zirconium?
Zirconium oxide (Zirconia) is an extremely tough ceramic with a hardness of >9 Mohs which makes it and excellent material for extreme wear, high temperature and harsh environment applications.
What are the irradiation-induced dimensional changes in zr-2nb?
The irradiation-induced dimensional changes in Zr-2.5Nb are irradiation creep and irradiation growth. Irradiation creep is the change in shape due to stress and fast neutron flux, whereas irradiation growth is the shape change at constant volume in a fast neutron flux without external stresses.
Can zr-2nb be used in light water reactors?
In a recent report from the Electric Power Research Institute, Zr-2.5Nb was identified as one of the candidate materials for use in normal structural applications in light-water reactors owing to its increased resistance to irradiation-induced degradation as compared with currently used materials.
What causes nodular corrosion of Zr-Nb alloys?
The cause of the nodular corrosion of the Zr-Nb alloys may be the result of the alloys’ sensitivity to oxygen in the environment as discussed in Section 5.2. In addition, unlike uniform corrosion that exhibits strong temperature dependence, nodular corrosion shows very small temperature dependence [ 2 ].
How does irradiation affect corrosion of Zircaloy-2 and ZR-2?
Urbanic et al. [ 43] investigated the effect of irradiation on corrosion of Zircaloy-2 and Zr-2.5Nb under both oxygenated coolant conditions and hydrogenated (low oxygen) conditions. Zr-2.5Nb is sensitive to dissolved oxygen in the water both under irradiation and in the absence of irradiation.