Wood's Metal: A soldering alloy with a melting point of 343K and an approximate composition of Bi4Pb2SnCd.
Galinstan: A material useful for thermal transfer. It has a thermal capacity of 16.5W/mK, and melting point of 254K. It's composition is Ga7In2Sn.
Sodium Potassium (NaK): Another material useful for thermal transfer, with a thermal capacity of 22.4W/mK and melting point of 261K. It is currently in GTCEu, but could use a composition update to Na2K8.
Production
These materials would be mixed from components in a mixer. Galinstan and NaK would produce a liquid.
Details
Wood's Metal: A soldering alloy with a melting point of 343K and an approximate composition of
Bi4Pb2SnCd.Galinstan: A material useful for thermal transfer. It has a thermal capacity of 16.5W/mK, and melting point of 254K. It's composition is
Ga7In2Sn.Sodium Potassium (NaK): Another material useful for thermal transfer, with a thermal capacity of 22.4W/mK and melting point of 261K. It is currently in GTCEu, but could use a composition update to
Na2K8.Production
These materials would be mixed from components in a mixer. Galinstan and NaK would produce a liquid.
Sources
https://en.wikipedia.org/wiki/Wood%27s_metal https://en.wikipedia.org/wiki/Galinstan https://en.wikipedia.org/wiki/Sodium%E2%80%93potassium_alloy