Production and Properties
Commercial non-nuclear grade zirconium typically contains 1–5% of hafnium, whose neutron absorption cross-section is 600x that of zirconium. Hafnium must therefore be almost entirely removed (reduced to < 0.02% of the alloy) for reactor applications.
Zirconium and zinc are found in magnesium alloys used in plane, car and spacecraft construction. Zirconium is used to lower the metal grain size, increasing the metal’s hardness.
Nuclear-grade zirconium alloys contain more than 95% Zr, and therefore most of their properties are similar to those of pure zirconium. The absorption cross section for thermal neutrons is 0.18 barn for zirconium, which is much lower than that for such common metals as iron (2.4 barn) and nickel (4.5 barn). The composition and the main applications of common reactor-grade alloys are summarized below. These alloys contain less than 0.3% of iron and chromium and 0.1–0.14% oxygen.
| Alloy | Sn, % | Nb, % | Vendor (country) |
Component | Reactor type |
|---|---|---|---|---|---|
| Zircaloy 2 | 1.2–1.7 | – | All vendors | Cladding, structural components | BWR, CANDU |
| Zircaloy 4 | 1.2–1.7 | – | All vendors | Cladding, structural components | BWR, PWR, CANDU |
| ZIRLO | 0.7–1 | 1 | Westinghouse | Cladding | PWR |
| Zr Sponge | – | – | Japan and Russia | Cladding | BWR |
| ZrSn | 0.25 | – | Westinghouse | Cladding | BWR |
| Zr2.5Nb | – | 2.4–2.8 | – | Pressure tube | CANDU |
| E100 | – | 0.9–1.1 | Russia | Cladding | RBMK |
| E125 | – | 2.5 | Russia | Pressure tube | RBMK |
| E635 | 0.8–1.3 | 0.8–1 | Russia | Structural components | RBMK |
| M5 | – | 0.8–1.2 | Areva | Cladding, structural components | PWR |
*ZIRLO stands for zirconium low oxidation.
Read more about this topic: Zirconium Alloy
Famous quotes containing the words production and, production and/or properties:
“Production and consumption are the nipples of modern society. Thus suckled, humanity grows in strength and beauty; rising standard of living, all modern conveniences, distractions of all kinds, culture for all, the comfort of your dreams.”
—Raoul Vaneigem (b. 1934)
“To expect to increase prices and then to maintain them at a higher level by means of a plan which must of necessity increase production while decreasing consumption is to fly in the face of an economic law as well established as any law of nature.”
—Calvin Coolidge (1872–1933)
“The reason why men enter into society, is the preservation of their property; and the end why they choose and authorize a legislative, is, that there may be laws made, and rules set, as guards and fences to the properties of all the members of the society: to limit the power, and moderate the dominion, of every part and member of the society.”
—John Locke (1632–1704)