![]() | This ![]() It is of interest to the following WikiProjects: | ||||||||||||||||||||
|
![]() | This article is written in British English, which has its own spelling conventions (colour, travelled, centre, defence, artefact, analyse) and some terms that are used in it may be different or absent from other varieties of English. According to the relevant style guide, this should not be changed without broad consensus. |
Good evening. I want to know the reference regarding the vapour pressure of the alloy at 500°C. Thank you. —Preceding unsigned comment added by 203.199.205.25 ( talk)
How much is in a typical household thermometer? What is the commercial price in bulk? What sorts of sources sell? - 71.174.182.182 ( talk) 01:11, 22 May 2009 (UTC)
Here is a speculative explanation: Galinstan is a commercial product! The company wants to sell it and advertise it as positively as possible! It is possible that Galinstan inside a thermometer don't freeze above −19°C. Because of metastable and coated insight the thermometer by Ga2O3. But this should not be mixed up by its real melting point! I doubt that it contains mercury or alkali metals which could lower its melting point to −19°C! Regards, Achim1999 ( talk) 11:19, 23 June 2009 (UTC)
Please check these data to the reference of the Ga : In : Sn eutectic which has a composition of 0.596 : 0.260 : 0.144 by weight and a melting point of 10.8°C. [1] Either Galinstan has a freezing point of 11°C or contains further undisclosed material! — Preceding unsigned comment added by Achim1999 ( talk • contribs)
Would you please either correct the data are delete the wrong value?! This is a ridiculous, too-low value for the ternary any(!) alloy made of Ga, In, and Sn. Achim1999 ( talk) 17:18, 23 June 2009 (UTC)
I copied this from a high quality German reference: “Aus der DD-PS 21 490 ist es bekannt, dass Vierstofflegierungen aus Gallium, Indium, Zinn, und Zink besonders niedrig schmelzen, nämlich bis etwa 8,5 C herab.” [2]
So, minimal 8.5°Celsius, including Zn! Regards, Achim1999 ( talk) 17:34, 23 June 2009 (UTC)
Eutectic of 59,6% Gallium, 26% Indium und 14,4% Tin has a melting point of 11°C . The reference gives also two other compositions and two melting points which are all of the given Galinstan composition. So Galinstan is not the Eutectic. Normaly the “eutectic” has the lowest melting point. The patent is the last place in that cases where to find the truth.
I had to remove [the above comment] from the main article; I have no idea what it was doing in there. I don't know who posted it, though, but I know it should be here on the discussion page and not in the article itself. — Preceding unsigned comment added by 65.12.192.70 ( talk) 18:05, 26 February 2010 (UTC) ; original comment added to article by 129.70.14.241
I noticed that the melting point controversy section in the article states that eutectic compositions are the lowest melting compositions. While this is always true for binary mixtures, it is not a guarantee that a specific eutectic point for a given mixture will be the lowest melting temperature possible for a given pressure. In other words: For mixtures with more than two components, there will almost certainly be a eutectic "surface" in the composition "space" that occurs over a range of temperatures, one or more of which would be the lowest. I have yet to find a ternary mixture with a single eutectic point.
I think the confusion over this likely due to not understanding the real meaning of what a eutectic composition is: A eutectic composition has the same composition on either side of the solid-liquid-equilibrium (SLE) phase boundary. That is all it means. One can think of a eutectic as the SLE analog of an azeotrope in a VLE. There can be low melting, high melting, and asymptotic eutectics, just as there are low boiling, high boiling, and asymptotic azeotropes. More often it is the low melting eutectics that are of common interest given the wider application in solders and liquid metal bearings. High melting eutectics are occasionally used to make alloys for high temperature applications, but high temperature tolerance designs are usually done with an error margin that exceeds any need for the high production standards needed to squeeze out that last few degrees of solid state.
If I have any time later I'll put something together for the main article to clear things up. In the meantime, hopefully this'll motivate someone else to get started on it.
As an aside on the January 2010 hysterics: Galinstan may be a registered trademark for a German company, but in-kind with the vernacular dilution of brand names like Kleenex, Band-Aid, Google, etc., it is a common means for referencing any eutectic mixture of these three specific metals. Its common use is more than enough reason to maintain an article describing it. Also, an MSE ought be cognizant of the degrees of freedom involved in the thermodynamics of a ternary mixture. The claim that there is a single eutectic composition for a ternary mixture is worse than the purported bias. But that's just my opinion; I could be wrong./ denis_miller_rant
Xenomancer ( talk) 23:18, 11 January 2013 (UTC)
Ternary eutectic is 66,0% Ga : 20,5 %In : 13,5 %Sn, with melting at 10.7±0.3°C. [1] S-Ene ( talk) 16:30, 18 April 2015 (UTC)
In the scientific publication "Gallium Safety in the Laboratory", L. C. Cadwallader states that Galinstan ... boils at about 2300°C. The Safety Data Sheet published by Geratherm simply states that the boiling point of Galinstan is greater than 1300°C.
The author of this diagram (Peter Dow) wonders if rather than boil from liquid galinstan into "gaseous galinstan", a dissociation of galinstan into its elements occurs at galinstan's boiling or dissociation temperature, namely gaseous gallium, gaseous indium, and tin vapour which could condense into liquid tin at temperatures below the boiling point of tin? Or is there a stable temperature range for molecular gaseous galinstan above galinstan's boiling point and if so what is galinstan's dissociation temperature? Anyway: Internet searches are not turning up much in the way of information about the boiling behaviour of galinstan so this diagram if nothing else can highlight the lack of published detail on this and if someone knows and wants to let the rest of us know, that would be kind. Thanks. Peter Dow ( talk) 14:33, 9 November 2010 (UTC)
Perhaps somewhat carelessly, I simply assumed the values for the boiling points of the elements which were given in the Wikipedia pages for the elements gallium, indium and tin would be about right so I used those values for my diagram.
Now it seems there is a big disagreement as to the boiling point values especially for gallium and tin. See the discussion pages for Gallium and Tin but we are talking hundreds of degrees of a difference so I am now doubting the values given on the Wikipedia pages and therefore doubting the accuracy of my own diagram. One of my old text books gives values there which correspond to the Chemical Elements website at first glance. On the other hand, another of my text books gives different values again. Disagreement all around it seems.
I would like to suggest that Wikipedia has got those boiling point temperatures for gallium and tin far wrong and to invite editors to comment. Peter Dow ( talk) 18:31, 9 November 2010 (UTC)
I have had reported to me different values from the same "reliable source", from different editions of the same handbook. Why is one source more reliable than the other? It seems to me that each of us may be taking an arbitrary decision about which source to rely on. Peter Dow ( talk) 00:29, 12 November 2010 (UTC)
Indeed. A little bird tells me that a review of the CRC Handbook values may be in the offing. My web search found a very relevant scientific paper "The Vapor Pressure of Indium, Silver, Gallium, Copper, Tin, and Gold Between 0.1 and 3.0 Bar" by F. Geiger, C. A. Busse and R. I. Loehrke, published 1987 in International Journal of Thermophysics, Vol. 8, No. 4 and this has inspired me to revise my diagram and to upload a second version. Peter Dow ( talk) 18:06, 13 November 2010 (UTC)
This article is missing a NFPA 704 diamond. As far as I know, chemicals used in industry must have one of these, though admittedly I don't know all the law details. But in my work experience every chemical used in factories and labs has one of these posted somewhere, so the data for this chemical should be available somewhere. I cant seem to find it on the web, but also I don't read German. In any case, this is a well established indicator of danger in handling and using chemicals, so should be a basic part of all chemical descriptions. I also note that many (most?) other chemicals listed in Wikipedia, do have these (iridium, lead, sulfuric acid, to name just a few).
Perhaps the problem is that this chemical is made (exclusively?) by Geratherm Medical AG, which may not be constrained by NFPA 704, the latter probably being a USA law.
Also, looking at the safety data sheet on the Geratherm Medical AG, this does not seem to be "totally safe" chemical, which is interesting in that it is used in thermometers, touted as "environmentally friendly" (I just bought one of these). Perhaps the lesson is that "environmentally safe" chemicals can still be toxic to humans. Though probably this chemical is less toxic to humans and other animals, than Mercury.
Please pardon me if this post is formatted improperly, or improper in content, as this is my first post on Wikipedia. Pduerig ( talk) 01:01, 9 December 2010 (UTC)
There is no "melting point controversy". A wealth of peer-reviewed sources state that the eutectic temperature of Gallium-Indium-Tin is close to 11 C. The trademark holder's claim is a lie, pure and simple.
The same sources will also tell you that the thermal conductivity of eutectic GaInSn is around 25 C, not 16.5 C. However, many less reliable sources state 16.5 C, almost certainly having got their information from this page.
If there are no objections, I intend to rework this page by creating a second page (title "Eutectic Galllium-Indium-Tin"). The current page will be reduced to a single paragraph which explains the trademark and mentions the melting point claim (and that it is without all evidence). It will link to the scientifically accurate "Eutectic Gallium-Indium-Tin" page. In the new page, based on this one, I will also review/correct all data, in accordance with multiple peer-reviewed papers. I will not remove the work of others (except where it is in stark disagreement with multiple peer reviewed papers), nor will I make significant additions.
Please object within 7 days if you do not approve of the proposed changes. Barneypitt ( talk • contribs) 13:34, 2 December 2018 (UTC)
I certainly didn't deliberately delete any sign or bot signature. I moved the original as I realised it could be placed better, deleted anything bot added, and assumed the second edit (the move) would get bot added again. I can see a signature and timestamp now(?).
There would be a need to add any toxic, reactive or radioactive ingredients to the material data safety sheet. Mercury, cadmium, lead, rubidium, cesium, potassium, sodium, lithium, thallium are all ruled out, therefore. Bismuth has negligible effect on melting points of gallium-rich alloys and none on eutectic GaInSn. Silver, copper, zinc and antimony all have mild melting point lowering effects on eGaIn, but simply adding more and more high-melting point impurities to the existing tin impurity (in any reasonable combination) gets you very rapidly diminishing returns, and very quickly causes increases in melting point if any sizable quantities are added. So what is the secret sauce which purports to cause a 29.5 (!) degree lowering in melting point? Pixie dust?
So is there any paper which actually verifies the melting point of commercial Galinstan, rather than reiterates the manufacturer claim? Isn't it somewhat odd that the trademark holders only make Galinstan thermometers which read near body temperature, and that they don't utilise what would frankly be the metallurgic miracle of the century for anything else?
Or is it more likely that the claim is inaccurate? Or refers to some temporary supercooling (usual for GaInSn) followed by eventual freezing?
I like a mystery too - but I don't like unverified trademark claims being reported ever more widely around the internet as time passes, because the go-to source of information repeats the unverified claim?
I have a proposal. I'll buy a Geratherm Galinstan thermometer. I'll unbox it, break it, freeze the Galinstan, heat it till it melts, take temperatures with a digital thermometer, film it all in a continuous (very boring!) take, and post on YouTube. Would that qualify as a reliable refutation of the claim? Barneypitt ( talk) 11:23, 9 December 2018 (UTC)
Is it miscible with mercury? 188.26.22.131 ( talk) 15:34, 8 April 2011 (UTC)
Should galinstan be spelled with a capital first letter as it is know in the article? Ulflund ( talk) 11:30, 30 May 2012 (UTC)
While I can appreciate many would correctly consider weight percent (wt%) to be the common assumption of a layperson, for sake of clarity it should be properly noted that the commonly sold composition given is indeed by mass, (ex. see GalliumSource). I will make the (admittedly small) edit in a moment's time, but I thought it better to leave the rationale behind it here. Xenomancer ( talk) 17:06, 11 January 2013 (UTC)
Is it possible to run a Hewittic mercury arc rectifier with Galinstan, instead of Hg? Those big glass octopus were highly efficient, like 86% or more, worked reliably for decades and looked cute in a way (whch may be important in post-industrial society). They were everywhere, powering movie theatres, lifts, escalators, trams, and cranes.
Yet the "Superfund" nature of a quart of liquid Hg needed for their operation led to the adoption of shorter-lived semiconductors. An alternative filling could bring them back to life. 82.131.236.19 ( talk) 12:23, 4 April 2015 (UTC)
I just came across an interesting paper investigating the characteristics of Galinstan. It suggests experimental evidence that the MELTING point is indeed 11°C, but that it can be readily supercooled to -10°C before re-solidifying (all at 1 atm). [2] 193.53.93.14 ( talk) 13:43, 7 January 2022 (UTC)
References