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As quoted in an online version of: David R. Lide (ed), CRC Handbook of Chemistry and Physics, 84th Edition.CRC Press. Boca Raton, Florida, 2003; Section 4, Properties of the Elements and Inorganic Compounds; Physical Properties of the Rare Earth Metals
Manganin is a trademarked name for an alloy of typically 84.2% copper, 12.1% manganese, and 3.7% nickel.It was first developed by Edward Weston in 1892, improving upon his Constantan (1887).
Silver, although it is the least resistive metal known, has a high density and performs similarly to copper by this measure, but is much more expensive. Calcium and the alkali metals have the best resistivity-density products, but are rarely used for conductors due to their high reactivity with water and oxygen (and lack of physical strength).
No other metal is verified to be more naturally diamagnetic than bismuth. [19] [22] (Superdiamagnetism is a different physical phenomenon.) Of any metal, it has one of the lowest values of thermal conductivity (after manganese, neptunium and plutonium) and the highest Hall coefficient. [23] It has a high electrical resistivity. [19]
This alloy has, for example, an adequately high strain sensitivity, or gauge factor, which is relatively insensitive to strain level and temperature. Its resistivity (5.00 × 10 −7 Ω·m) [2] is high enough to achieve suitable resistance values in even very small grids, and its temperature coefficient of resistance is fairly low.
The resistivity of different materials varies by an enormous amount: For example, the conductivity of teflon is about 10 30 times lower than the conductivity of copper. Loosely speaking, this is because metals have large numbers of "delocalized" electrons that are not stuck in any one place, so they are free to move across large distances.
Rhodium is a hard, silvery, durable metal that has a high reflectance. Rhodium metal does not normally form an oxide, even when heated. [25] Oxygen is absorbed from the atmosphere only at the melting point of rhodium, but is released on solidification. [26] Rhodium has both a higher melting point and lower density than platinum.
Nichrome, a non-magnetic 80/20 alloy of nickel and chromium, is the most common resistance wire for heating purposes because it has a high resistivity and resistance to oxidation at high temperatures, up to 1,400 °C (2,550 °F). When used as a heating element, resistance wire is usually wound into coils.