Busting myths about Tin, Magnets and their reactivity:
Tin comes in two Crystal structures: Tetragonal (White Tin), and Diamond Cubic (Gray Tin).
“β-tin (the metallic form, or white tin), which is stable at and above room temperature, is malleable. In contrast, α-tin (nonmetallic form, or gray tin), which is stable below 13.2 °C (56 °F), is brittle.”
Gray Tin is diamagnetic meaning repels a magnetic field. White Tin is paramagnetic meaning draws into a magnetic field.
Source: http://en.wikipedia.org/wiki/Tin
“Strong paramagnetism also decreases with rising temperature because of the de-alignment produced by the greater random motion of the atomic magnets. “
Source: http://www.universetoday.com/84358/paramagnetism/
Magnetization
“The magnetization of a magnetized material is the local value of its magnetic moment per unit volume, usually denoted M, with units A/m. It is a vector field, rather than just a vector (like the magnetic moment), because different areas in a magnet can be magnetized with different directions and strengths. A good bar magnet may have a magnetic moment of magnitude 0.1 A•m2 and a volume of 1 cm3, or 1×10−6 m3, and therefore an average magnetization magnitude is 100,000 A/m. Iron can have a magnetization of around a million amperes per meter. Such a large value explains why iron magnets are so effective at producing magnetic fields.”
Source http://en.wikipedia.org/wiki/Magnet
To consider the depth of variability goes even further: Different types of magnets may have different classifications OF that type of magnet. “Permanent Magnets can further be classified into four types based on their composition: 1. Neodymium Iron Boron (NdFeB or NIB) 2. Samarium Cobalt (SmCo) 3. Alnico 4. Ceramic or Ferrite”
Source: http://www.howmagnetswork.com/types.html
The strength of magnetism will vary between different elements including how an element will respond to certain magnetic types and even temperature can change reactivity (between the element, magnet or both). As a side thought, I don’t suppose brittle gray tin would be ideal for a solder, let alone casting, no? Are you really sure you know exactly what’s in your pewter, solder, linotype? Or how lead (being a softer metal) mixed with gray tin (at whatever amount you deem worthy) would react as a ballistic alloy? Or if you’re at the right temp to test it (or if temperature will matter with the tin type you may have present)? Or if you have a mix between white and gray tin? Or if the alloys mixed with your specific tin type hasn’t changed its Diamagnetic/Paramagnetic strength? Or if the Diamagnetic strength was even reactive enough to begin with? To conclude there’s no such thing as “plain tin”. Stating that “tin is an element” is irrelevant, it can have various crystal structures that will vary in chemical and magnetic reactivity and even density depending on its crystal type and mixture with other alloys, their amount, etc. Pure-white-tin is malleable, will melt at 449.6 degrees Fahrenheit, it’s stable, ideal for soldering and casting; and a magnet will stick to pure white tin. Thanks for reading and LET THE ARGUMENTS BEGIN!!!!!
-Steven
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Originally Posted by mold maker
I didn't know tin had such a long history.
) The samples did behave differently initially with the diluted alloy flattening easier at first but once the un-diluted sample began to flatten it ended up the same thickness but it did seam to take more blows to get there. OK, so they're not exactly the same but more similar than the amount of dilution would have made me expect.
