| Lake Shore offers a complete line of cryogenic accessories for sensor installation and general-purpose cryogenic use. |
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| Cryogenic Wire and Cable |
| Used to minimize heat leak into the sensor and cryogenic system, cryogenic wire has a much lower thermal conductivity (and higher electrical resistivity) than copper wire. |
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The most common type of cryogenic wire is phosphor bronze. This wire is available in one-, two-, and four-lead configurations. Four-lead configurations are available as Quad-twist™ (two twisted pairs) or Quad-lead™ (ribbon). Wire gauge is 32 or 36 AWG, with polyimide or polyvinyl formal (Formvar®) used to insulate the wires. |
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| Other common cryogenic wires and coaxial cables include manganin, nichrome heater wire, and HD-30 heavy duty copper wire. For high-frequency signals, Lake Shore provides various coaxial cables: ultra miniature coaxial cables and semi-rigid coaxial with a stainless steel center conductor. |
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| Solder |
The most common electrical connections are solder joints. Solder can also be used to install various sensors to improve thermal heat sinking. Common solders are indium solder and 90/10 Pb/Sn. Indium solder is used for various applications including sensor installation to provide excellent thermal contact with the sample. 90/10 Pb/Sn solder is used for applications requiring a higher temperature (liquidus point of 575 K and solidus point 458 K). Ostalloy® 158 solder is used as a seal for demountable vacuum cans and electric feedthroughs in cryogenic systems.
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| Epoxy, Thermal Grease, and Varnish |
| Thermal greases and epoxies are used to install and fasten sensors, while providing thermal contact and/or electrical insulation, with the sample. Epoxy can be used for mechanical attachment and joints. |
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The most common varnish for cryogenic installations is VGE-7031 varnish. It has good chemical resistance, bonds to a variety of materials, and has a fast tack time. Stycast® 2850FT is composed of a black epoxy resin, and has a thermal expansion coefficient that is matched to copper. A silver-filled, low-temperature conducting epoxy provides excellent strength, along with electrical and thermal conductivity.
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Thermal grease, Apiezon N and Apiezon H, is suitable for enhancing thermal contact, especially for sensors inserted into cavities. Apiezon N is for low temperature applications, while H is for high temperature.
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| Miscellaneous Cryogenic Accessories |
| Lake Shore also supplies heat sink bobbins, a beryllium oxide heat sink chip, and a four-lead resistance sample holder. Cartridge heaters and vacuum feed through products are also available. |
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