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Home/Sitemap · Search · you are here: Forum =>letter 0740 Tin Pest or Tin Disease
---- The thread quickly drew the attention of students and soon became focused more on schoolwork than on the industrial implications of the issue.
We are looking for detailed information regarding a phenomenon called "tin pest", or "tin disease". This occurs mainly at specific temperature ranges when the pure tin plating spontaneously transforms from one crystalline form to another and flakes off. Any help you can be will be much appreciated. I believe this was first observed at NASA Goddard, but I'm not sure. This effect has rendered pure tin unacceptable for space use under certain conditions and I need to know exactly what conditions will precipitate this phenomena. Thanks. Bob Denney
Dear Bob,
Try "Tin in Cold Service" Leaflet No. 55 published by the Tin research Association at Tin Research inc Columbus Ohio (Though they might have moved it's an old leaflet I've got). If you have problems getting it I could fax you a copy. Regards Richard Guise Ed. note: We found the International Tin Research Institute at http://www.itri.co.uk
We plate alkaline tin (dull) that contains a percentage of bismuth for Collins Rockwell that serves the same purpose you are trying to solve. It works for them. We plate on aluminum, steel, copper, stainless steel. Todd Huehn
- I was looking for 'tin pest' on the web because I have a very old tin teapot (I guess about 150 plus years old) and it lost its shiny tin cover. Lately it was sort of vibrating and my wife mentioned it to my father, who has graduated from a Dutch Nautical Institute before WW2. He was the one who mentioned the words 'tin pest' to me and this is why I looked it up. Please note that this teapot has never been in temperatures below 10 degrees Celsius and still it was subject to flaking, etc. It is just very old. Maybe this knowledge is of help. Siets Meijer - It was vibrating!? I think your teapot has a special variety of tin pest closely related to the larva worms in jumping beans, Siets
- So sorry, just vibrating, no larvae or jumping beans =). Siets Meijer Siets Meijer --- I am doing a lab report for my chemistry class. The extension question is as follows: Sometimes extreme physical changes result in permanent changes in the nature of a substance. Investigate the phenomenon of tin pest. What causes this physical change? Could anyone help me out? I am desperate! Jen B
- Napoleon, during his advance on Moscow during the severe Russian winter experienced this "disease", (or rather his poor squaddies). The soldiers' buttons, made of tin, crumbled to dust. This is because Tin goes through a change in crystal form at low temperatures to a less crystalline (more amorphous) form. ROSS MACDONALD . Tin is stable in the beta form (allotrope) at room temperatures but will change to the alpha form at low temperatures (actually below 13.2 deg C, though much lower temperatures are needed for observable transition, the lower the temperature the faster the transition). The alpha form has a much weaker structure, hence the buttons of Napoleon's troops turning to dust in the harsh Moscow winter. When the temperature rises the situation becomes worse (for buttons) because the transition back to the beta form introduces crystalline faults. "Chemistry of the Elements" [link is to book info at Amazon], Greenwood and Earnshaw, will explain further. Angie Jamison . I am a student at Chamblee High School in Georgia. I have a Chemistry question for you. I was wondering if you could help me with it. The question is Sometimes extreme physical changes result in permanent changes in the nature of a substance. Investigate the phenomenon of tin pest. What cause this physical change? Would you please help me in I really could use it Thanx P.S. If possible can email me back tomorrow or ASAP. Thank You. Aisha
. i am also a student at Chamblee high and from the information i have gathered i think tin pest is that when pure tin is exposed to temperatures below 10 degrees Celsius it deteriorates or flakes off into a powder. n. y.
. Hi, guess what, I had the exact same chemistry question. (I guess chemistry teachers are big on sharing.) Anyway this site helped a lot. Thankee kindly. Elenor D awww, shucks, ma'am, we're just turning red faster than a tin can goes from beta to alpha in North Dakota come January. - The editors of finishing.com . wow!, this question about tin pest on chemistry labs seems to be a pretty popular question.. I myself had the same exact question to answer. I was able to gather just about all the info i needed from this site. Well, I would just like to say thanks to all those experts out there willing to share their time to help out us students. Thanks guys! Mike A
. I just think it's funny how we all have the same question. I sure hope you all are right, though. If all the teachers can conspire against us to give us this lab, we can conspire with them and share answers! B.T.W., wasn't that a fun lab!!! Anyone have any accidents with the silver nitrate? Matthew H . I, just like every other student who took time to read this page, not only had fun reading the redundancy of fellow students, but learning the answer to a much-asked question. Thank you for your information, and good luck to other high school chemists! Thanks again, Meg P.S. Does anybody else think they should update the questions is text books?!? Meg E Ed. note: nah..... . I think it's cool how everyone has the same lab book! This page was really helpful. Now i know why Napoleon never reached Moscow. His troops couldn't fight AND hold up their buttonless britches! Science and History class come together! Tiff G . Tin pest, as many people have said above, is caused by a change of state in the tin. The tin we all know and love is normally bright silver and crystalline. If you get a piece of pure tin and bend it, it will give out a noise. This is called "tin crying" and is caused by the tin crystals distorting against each other. However, if tin is exposed to low temperatures the silver grey metal changes from the beta state (or crystal form) to the alpha state (or crystal form). This theoretically occurs at about 18 C, but the impurities in the tin force this temperature down - the more impurities, the lower the temperature. It is very difficult to get pure tin, most commercial tin is about 99.5% pure and this is enough to drop the transition temperature to quite low levels. Alpha tin is a manky grey powder. There is a story, which I cannot confirm, that at the end of the C19th a Russian Czar had a shipment of tin sent across Russia and when it arrived it was the horrible grey type. The Czar's officials thought the man who transported it had robbed the Czar and he was put to death. It is also claimed that Napoleon's troops suffered from tin pest when the buttons on their tunics fell to pieces because of the very low temperatures. I cannot confirm this because I wasn't around then! I hope this is of interest and helps anyone who is eager to improve their continued education.
+ Tin pest has been well know in the north of Sweden as the Sami peoples spin thread from it to decorate their clothes with. The tin of today can take -40 degrees or more (that the same on both F. and C. scales) The tin is first purified and then a couple of percent of pure silver is added. This information comes from a book called "TENNTRADSBRODERIER" by Mona Callenberg. She claims that tin has a tetra cristalen above 13 degrees C. and s cubical cristalen form. Tim Honn + Monmouth Academy's Junior Chemistry Class was lucky enough to have that same text book that is so often mentioned throughout this website. I too scanned the internet in search of information on Tin Pest, and was thrilled to find a single site that completely answered my question! I appreciate everything you've provided and hope that you understand how much you've helped high school students around the world!! THANK YOU!
+ I have a son in high school taking Junior chemistry too, Rebecca. Won't it be funny if he gets the same question and searches the billions of pages of the world wide web, only to find his father's site :-)
++ I have found some interesting and similar stuff about solders and soldering in "how to do" type literature published by Johnson Mathey Metals (dating from the 1950's). It seems that a little silver will improve things greatly. The consequences of what might happen to a space satellite going into earth shadow when cheap solder has been used hardly bear thinking about! David Benyon ++++ Hello all! I am a high school student doing research of my own on Tin. I just thought I would add that other sources have stated that tin changes colour at about 13.2 degrees Celsius. Also, here is another interesting fact - in Medieval Europe, when tin organ pipes turned colour because of temperature change, it was thought to be the "devil's work." Keep up the great work and thanks for a great website! Sarah F
++++ I have a copy of "Tin: Its Mining, Production, Technology & Applications" [link is to info about the book at Amazon], copyright 1949 by C. L. Mantell The author devoted several paragraphs to tin pest. White tin (tetragonal) is stable down to 18°C. Below that, the stable phase is gray tin (cubic). The transformation is very slow, so tin objects do not spontaneously crumble into gray powder. The transformation begins to accelerate rapidly at -20°C, peaking at -45°C. The implications are large for electronic devices used in cold climates. Old solders were tin-lead, while recent solders are either tin-antimony or tin-silver. Joseph Greene
+++++ Very interesting discussion. I have been involved in the soldering industry for 30 years and have some experience of the problem in the electronics arena. Certainly NASA did report this problem back in the sixties which lead to antimony being made a requirement in the then federal QQS solder specifications even though the alloy used was not pure tin but 60/40 Sn/Pb. Adding between 0.2 and 0.5%Sb made the alloys much less prone tin pest. I am sure it didn't prevent it totally but delayed the onset to a lower temperature. With the global transition to lead free solders the likelihood of tin pest occurring could increase. Space applications will continue to use lead containing solders for the foreseeable future though. Chris Ward +++++ As mentioned in an earlier posting, there has been published a fairly popular book called
"Napoleon's Buttons: How 17 Molecules Changed History" [link is to info about book on Amazon], by P. Couteur and J. Burreson of British Columbia. In this book they make, or remake the claim, that one of the reasons for the defeat of Napoleon's Grande Armeé in Russia was that his solders had tin buttons. The argument is that in the cold of the Russian winter the normal, white tin turned to gray tin (tin pest), which has no structural integrity and as a result the solders could not keep their coats closed and this facilitated their freezing to death.
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