Product Code Database
Chromel is an alloy made of approximately 90% nickel and 10% chromium by weight that is used to make the positive conductors of ANSI Type E (chromel-constantan) and K (chromel-alumel) . It can be used at temperatures up to in oxidizing atmospheres. Chromel is a registered trademark of Concept Alloys, Inc. Concept Alloys, Inc. Intellectual Property retrieved 12 April 2016
| + Characteristics and properties of chromel (Ni, 90%; Cr, 10% by weight) | |
| Temperature coefficient | 0.00032 K−1 |
| Electrical resistivity | 0.706 μΩ m |
| Elongation at break | <44% |
| Izod impact strength | 108 J m−1 |
| Modulus of elasticity | 186 GPa |
| Tensile strength | 620–780 MPa |
| Density | 8.5 g cm−3 |
| Melting point | 1420 °C |
| Magnetic | Non-Magnetic |
| Coefficient of thermal expansion | 12.8×10−6 K−1 at 20–1000 °C |
| Maximum use temperature in air | 1100 °C |
| Thermal conductivity | 19 W m−1 K−1 at 23 °C |
Chromel-R was also produced as a woven fabric of chromel wires for improved flexibility compared to sheet metal. It was developed by Litton Industries for use by NASA in the Gemini program and .
The Gemini G4C spacesuit did not use Chromel-R as standard. However the Gemini 9 mission was to test the use of the Astronaut Maneuvering Unit, a free-flying 'rocket pack'. To protect against the hot exhaust of its hydrogen peroxide engine, Gene Cernan's suit was given additional protection with an over-trouser layer of Chromel-R. The spacewalk during this flight gave a number of problems, with Cernan overheating and finding the suit difficult to move in it, with "all the flexibility of a rusty suit of armor". (2025). 9781429971782, St. Martin's Press. ISBN 9781429971782 The Chromel-R layer was an integral part of the spacesuit,It may be seen being worn as the astronauts travel out to the launch pad, S66-34075.jpg although the confined Gemini capsule did not require much movement until the spacewalk. Once pressurised, the suit became difficult to move in.
Smaller patches of Chromel-R formed an outer layer of the Apollo spacesuit where abrasion resistance was needed. These patches can be seen as silver-grey areas over the white Beta cloth of the main suit. Using patches, rather than an entire garment, avoided the flexibility problems with Gemini. The upper areas of the overshoes, the gloves and patches beneath the life support backpack were of Chromel-R. Gold-plated open-weave Chromel-R mesh has also been used as the reflecting surface for compact-folding parabolic antenna on spacecraft.
target="_blank" rel="nofollow"> Materials properties of thermocouple wires sold by Omega Engineering, Inc.
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