Field's metal, also known as Field's alloy, is a fusible alloy that becomes liquid at approximately 62 °C (144 °F).[1] It is named after its inventor, Simon Quellen Field.[2] It is a eutectic alloy of bismuth, indium, and tin, with the following mass fractions: 32.5% Bi, 51% In, 16.5% Sn.[3]
When prepared, Field's metal can be melted in hot water. Field's metal is costly because its major component indium is expensive, priced at around double the price of silver.[4] Because it includes neither lead nor cadmium, it is much less toxic than Wood's metal. It can be used for small-run die casting and rapid prototyping.[5]
This alloy has been investigated as a possible liquid metal coolant in advanced nuclear power system designs.[6] Field's metal is also of interest to nanotechnology researchers.[7][8]
Although it is much less dangerous to use than other commonly melted metals, such as lead or aluminium, contact with Field's metal in the liquid state can cause third-degree burns. Indium has also been associated with Indium lung in workers frequently exposed to indium processing.
Similar alloys
Alloy | Melting point | Eutectic? | Bismuth % | Lead % | Tin % | Indium % | Cadmium % | Thallium % | Gallium % | Antimony % |
---|---|---|---|---|---|---|---|---|---|---|
Rose's metal | 98 °C (208 °F) | no | 50 | 25 | 25 | – | – | – | – | – |
Cerrosafe | 74 °C (165 °F) | no | 42.5 | 37.7 | 11.3 | – | 8.5 | – | – | – |
Wood's metal | 70 °C (158 °F) | yes | 50 | 26.7 | 13.3 | – | 10 | – | – | – |
Field's metal | 62 °C (144 °F) | yes | 32.5 | – | 16.5 | 51 | – | – | – | – |
Cerrolow 136 | 58 °C (136 °F) | yes | 49 | 18 | 12 | 21 | – | – | – | – |
Cerrolow 117 | 47.2 °C (117 °F) | yes | 44.7 | 22.6 | 8.3 | 19.1 | 5.3 | – | – | – |
Bi-Pb-Sn-Cd-In-Tl | 41.5 °C (107 °F) | yes | 40.3 | 22.2 | 10.7 | 17.7 | 8.1 | 1.1 | – | – |
Gallium | 30.0 °C (86 °F) | Pure metal | - | - | - | - | - | - | 100 | – |
Galinstan | −19 °C (−2 °F) | no | <1.5 | – | 9.5–10.5 | 21–22 | – | – | 68–69 | <1.5 |