Search results
Results from the WOW.Com Content Network
It is based on a planar zirconia element, but also incorporates an electrochemical gas pump. An electronic circuit containing a feedback loop controls the gas-pump current to keep the output of the electrochemical cell constant, so that the pump current directly indicates the oxygen content of the exhaust gas. This sensor eliminates the lean ...
The most common oxide is zirconium dioxide, ZrO 2, also known as zirconia. This clear to white-coloured solid has exceptional fracture toughness (for a ceramic) and chemical resistance, especially in its cubic form. [37] These properties make zirconia useful as a thermal barrier coating, [38] although it is also a common diamond substitute. [37]
Zirconia is also employed in the deposition of optical coatings; it is a high-index material usable from the near-UV to the mid-IR, due to its low absorption in this spectral region. In such applications, it is typically deposited by PVD. [23] In jewelry making, some watch cases are advertised as being "black zirconium oxide". [24]
The most common electrolyte, again similar to solid-oxide fuel cells, is a dense ionic conductor consisting of ZrO 2 doped with 8 mol-% Y 2 O 3 (also known as YSZ, ytrium-stabilized zirconia). Zirconium dioxide is used because of its high strength, high melting temperature (approximately 2700 °C) and excellent corrosion resistance.
One of the main uses of zirconium alloys is in nuclear technology, as cladding of fuel rods in nuclear reactors, especially water reactors. A typical composition of nuclear-grade zirconium alloys is more than 95 weight percent [ 1 ] zirconium and less than 2% of tin , niobium , iron , chromium , nickel and other metals, which are added to ...
Yttria-stabilized zirconia (YSZ) crystal structure. Yttria-stabilized zirconia (YSZ) is a ceramic in which the cubic crystal structure of zirconium dioxide is made stable at room temperature by an addition of yttrium oxide. These oxides are commonly called "zirconia" (Zr O 2) and "yttria" (Y 2 O 3), hence the name.
Scheme of a solid-oxide fuel cell. A solid oxide fuel cell (or SOFC) is an electrochemical conversion device that produces electricity directly from oxidizing a fuel. Fuel cells are characterized by their electrolyte material; the SOFC has a solid oxide or ceramic electrolyte.
Nuclear Fuel Complex supplies zircaloy clad uranium oxide fuel assemblies and zirconium alloy structural components for all 14 operating atomic power reactors in India. [2] The Hyderabad plant has a capacity to produce 250 tons of UO 2 per year and is expected to expand to a 600 tons per year capacity.