Liquid metal cooled reactor Clementine was the first liquid metal cooled nuclear reactor and used mercury coolant, thought to be the obvious choice since it is liquid at room temperature. However, because of disadvantages including high toxicity, high vapor pressure even at room temperature, low boiling point, producing noxious fumes when heated, relatively low thermal conductivity, and a high neutron cross-section, it has fallen out of favor. Sodium and NaK (a eutectic sodium-potassium alloy) do not corrode steel to any significant degree and are compatible with many nuclear fuels, allowing for a wide choice of structural materials. They do, however, ignite spontaneously on contact
Liquid metal ion source the gallium ion is sufficiently heavy for ion milling. The LMIS technique originated in the development of colloid thruster spacecraft propulsion systems. Research beginning in the early 1960s showed that liquid metal can generate large numbers of ions. By the early 1970s, these results spawned the development of LMIS ion microprobes. Initially, in the development of this technique, the liquid metal was supplied by a capillary tube. This method can be difficult to control at low emission currents. The technique of "blunt-needle" LMIS was discovered by accident in the early 1970s. For this method a thin-film of liquid metal is