Chromel R has a composition of Cr 20%, Ni 80%. 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 and
Apollo programs. 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". The Chromel-R layer was an integral part of the spacesuit, 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. ==References and notes==