From Wikipedia, the free encyclopedia
Galinstan on glass.jpg
Galinstan from a broken thermometer, easily wetting a piece of glass
Physical properties
Density (ρ)6.44 g/cm3 (at 20 °C)
Thermal properties
Melting temperature (Tm)-19 °C
Specific heat capacity (c)296 J·kg−1·K−1

Galinstan (R) is a brand name for a alloy composed of gallium, indium, and tin which melts at −19 °C (−2 °F) and is thus liquid at room temperature.[4][5] However, it is not a eutectic alloy but a near eutectic alloy.[5] In scientific literature, galinstan is also used as an acronym denoting the eutectic composition of the alloy of Ga-In-Sn, which melts at around +11 °C (52 °F).[5] The composition of both alloys is roughly the same, albeit the Galinstan (R), the technical product of a company, has likely additions of flux to improve flowability, reduce melting temperature, and reduce surface tension. The physical properties of the Galinstan (R) and the pure eutectic alloy EGaInSn thus differ slightly.[5]

Galinstan is composed of 68.5% Ga, 21.5% In, and 10.0% Sn (by weight).[6]

Due to the low toxicity and low reactivity of its component metals, in many applications, galinstan has replaced the toxic liquid mercury or the reactive NaK (sodiumpotassium alloy).


The name "Galinstan" is a portmanteau of gallium, indium, and stannum (Latin for "tin"). The brand name "Galinstan" is a registered trademark of the German company Geratherm [de].

Physical properties[edit]

Unlike mercury, galinstan tends to wet and adheres to many materials, including glass, which can limit its use as a direct replacement material in some situations.


The non-toxic galinstan replaces mercury in thermometers; the tube interior must be coated with gallium oxide to prevent it from wetting the glass.

Galinstan has higher reflectivity and lower density than mercury. In astronomy, it can replace mercury in liquid-mirror telescopes.[10]

Metals or alloys like galinstan that are liquids at room temperature are often used by overclockers and enthusiasts as a thermal interface for computer hardware cooling, where their higher thermal conductivity compared to thermal pastes, and thermal epoxies can allow slightly higher clock speeds and CPU processing power achieved in demonstrations and competitive overclocking. Two examples are Thermal Grizzly Conductonaut and Coolaboratory Liquid Ultra, with thermal conductivities of 73 and 38.4 W/mK respectively.[11][12] Unlike ordinary thermal compounds which are easy to apply and present a low risk of damaging hardware, galinstan is electrically conductive and causes liquid metal embrittlement in many metals including aluminum which is commonly used in heatsinks. Despite these challenges the users who are successful with their application do report good results.[13] In August 2020, Sony Interactive Entertainment patented a galinstan-based thermal interface solution suitable for mass production,[14] for use on the PlayStation 5.

Galinstan is difficult to use for cooling fission-based nuclear reactors, because indium has a high absorption cross section for thermal neutrons, efficiently absorbing them and inhibiting the fission reaction. Conversely, it is being investigated as a possible coolant for fusion reactors. Its nonreactivity makes it safer than other liquid metals, such as lithium and mercury.[15]

Galinstan is used as a liquid, deformable conductor in soft robotics and stretchable electronics. Galinstan can be used to replace wires, interconnects, and electrodes as well as the conductive element in inductor coils and dielectric composites for soft capacitors.[16]

X-ray equipment[edit]

Extremely high-intensity sources of 9.25 keV X-rays (gallium K-alpha line) for X-ray phase microscopy of fixed tissue (such as mouse brain), from a focal spot about 10 μm × 10 μm, and 3-D voxels of about one cubic micrometer, may be obtained with an X-ray source that uses a liquid-metal galinstan anode.[17] The metal flows from a nozzle downward at a high speed, and the high-intensity electron source is focused upon it. The rapid flow of metal carries current, but the physical flow prevents a great deal of anode heating (due to forced-convective heat removal), and the high boiling point of galinstan inhibits vaporization of the anode.[18]

See also[edit]


  1. ^ Hodes, Marc; Zhang, Rui; Steigerwalt Lam, Lisa; Wilcoxon, Ross; Lower, Nate (2014). "On the Potential of Galinstan-Based Minichannel and Minigap Cooling". IEEE Transactions on Components, Packaging and Manufacturing Technology. 4 (1): 46–56. doi:10.1109/tcpmt.2013.2274699. ISSN 2156-3950. S2CID 30876603.
  2. ^ a b c "Experimental Investigations of Electromagnetic Instabilities of Free Surfaces in a Liquid Metal Drop" (PDF). International Scientific Colloquium Modelling for Electromagnetic Processing, Hannover. March 24–26, 2003. Retrieved 2009-08-08.
  3. ^ a b ZHANG (2019). "Characterization of Triboelectric Nanogenerators". Flexible and stretchable triboelectric nanogenerator devices – toward self-powered ... systems. WILEY. p. 70. ISBN 978-3527345724. OCLC 1031449827.
  4. ^ Surmann, P; Zeyat, H (Nov 2005). "Voltammetric analysis using a self-renewable non-mercury electrode". Analytical and Bioanalytical Chemistry. 383 (6): 1009–1013. doi:10.1007/s00216-005-0069-7. PMID 16228199. S2CID 22732411.
  5. ^ a b c d Handschuh-Wang, Stephan; Gan, Tiansheng; Rauf, Muhammad; Yang, Weifa; Stadler, Florian J.; Zhou, Xuechang (December 2022). "The subtle difference between Galinstan (R) and eutectic GaInSn". Materialia. 26: 101642. doi:10.1016/j.mtla.2022.101642. S2CID 254003580.
  6. ^ Liu, Jing (2018-07-14). "Ch 5 Preparations and Characterizations of Functional Liquid Metal Materials". Liquid metal biomaterials : principles and applications. Yi, Liting. Singapore. p. 96. ISBN 9789811056079. OCLC 1044746336.
  7. ^ Liu, Tingyi; Kim, Chang-Jin "CJ" (2012). "Characterization of Nontoxic Liquid-Metal Alloy Galinstan for Applications in Microdevices". Journal of Microelectromechanical Systems. 21 (2): 448. CiteSeerX doi:10.1109/JMEMS.2011.2174421. S2CID 30200594.
  8. ^ Jeong, Seung Hee; Hagman, Anton; Hjort, Klas; Jobs, Magnus; Sundqvist, Johan; Wu, Zhigang (2012). "Liquid alloy printing of microfluidic stretchable electronics". Lab on a Chip. 12 (22): 4657–64. doi:10.1039/c2lc40628d. ISSN 1473-0197. PMID 23038427.
  9. ^ Handschuh-Wang, Stephan; Chen, Yuzhen; Zhu, Lifei; Zhou, Xuechang (2018-06-20). "Analysis and Transformations of Room-Temperature Liquid Metal Interfaces – A Closer Look through Interfacial Tension". ChemPhysChem. 19 (13): 1584–1592. doi:10.1002/cphc.201800559. ISSN 1439-4235. PMID 29539243.
  10. ^ Minerals Yearbook Metals and Minerals 2010 Volume I. Government Printing Office. 2010. p. 48.4. Extract of page 48.4
  11. ^ "Thermal Grizzly High Performance Cooling Solutions – Conductonaut". Thermal Grizzly. Retrieved 2019-12-18.
  12. ^ Wallossek 2013-10-21T06:00:01Z, Igor (21 October 2013). "Thermal Paste Comparison, Part Two: 39 Products Get Tested". Tom's Hardware. Retrieved 2019-12-18.
  13. ^ "Liquid Metal Laptop Cooling". YouTube. Archived from the original on 2021-12-22. Retrieved 2021-03-05.
  14. ^ "WIPO Patentscope: "WO2020162417 - Electronic apparatus, semiconductor device, insulating sheet, and method for manufacturing semiconductor device". Retrieved 2020-10-24.
  15. ^ Lee C. Cadwallader (2003). "Gallium Safety in the Laboratory" (preprint). {{cite journal}}: Cite journal requires |journal= (help)
  16. ^ Bury, Elizabeth; Chun, Seth; Koh, Amanda S. (2021). "Recent Advances in Deformable Circuit Components with Liquid Metal". Advanced Electronic Materials. 7 (4): 2001006. doi:10.1002/aelm.202001006. ISSN 2199-160X. S2CID 234217238.
  17. ^ Hemberg, O.; Otendal, M.; Hertz, H. M. (2003). "Liquid-metal-jet anode electron-impact x-ray source". Appl. Phys. Lett. 83 (7): 1483. Bibcode:2003ApPhL..83.1483H. doi:10.1063/1.1602157.
  18. ^ Töpperwien, M.; et al. (2017). "Three-dimensional mouse brain cytoarchitecture revealed by laboratory-based x-ray phase-contrast tomography". Sci. Rep. 7: 42847. Bibcode:2017NatSR...742847T. doi:10.1038/srep42847. PMC 5327439. PMID 28240235.


  • Scharmann, F.; Cherkashinin, G.; Breternitz, V.; Knedlik, Ch.; Hartung, G.; Weber, Th.; Schaefer, J. A. (2004). "Viscosity effect on GaInSn studied by XPS". Surface and Interface Analysis. 36 (8): 981. doi:10.1002/sia.1817. S2CID 97592885.
  • Dickey, Michael D.; Chiechi, Ryan C.; Larsen, Ryan J.; Weiss, Emily A.; Weitz, David A.; Whitesides, George M. (2008). "Eutectic Gallium-Indium (EGaIn): A Liquid Metal Alloy for the Formation of Stable Structures in Microchannels at Room Temperature". Advanced Functional Materials. 18 (7): 1097. doi:10.1002/adfm.200701216. S2CID 538906.