Tin cry is the characteristic sound heard when a bar made of
tin is bent. Variously described as a "screaming" or "crackling" sound, the effect is caused by the
crystal twinning
Crystal twinning occurs when two or more adjacent crystals of the same mineral are oriented so that they share some of the same crystal lattice points in a symmetrical manner. The result is an intergrowth of two separate crystals that are tightl ...
in the metal. The sound is not particularly loud, despite terms like "crying" and "screaming". It is very noticeable when a hot-dip tin-coated sheet metal is bent at high speed over rollers during processing.
Tin cry is often demonstrated using a simple science experiment. A bar of tin will "cry" repeatedly when bent until it breaks. The experiment can then be recycled by melting and recrystallizing the metal. The low melting point of tin, , makes re-casting easy. Tin
anneals at reasonably low temperature as well, normalizing tin's
microstructure of crystallites/grains.
Although the cry is most typical of tin, a similar effect occurs in other metals, such as
niobium
Niobium is a chemical element; it has chemical symbol, symbol Nb (formerly columbium, Cb) and atomic number 41. It is a light grey, crystalline, and Ductility, ductile transition metal. Pure niobium has a Mohs scale of mineral hardness, Mohs h ...
,
indium
Indium is a chemical element; it has Symbol (chemistry), symbol In and atomic number 49. It is a silvery-white post-transition metal and one of the softest elements. Chemically, indium is similar to gallium and thallium, and its properties are la ...
,
zinc
Zinc is a chemical element; it has symbol Zn and atomic number 30. It is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic tabl ...
,
cadmium,
gallium
Gallium is a chemical element; it has Chemical symbol, symbol Ga and atomic number 31. Discovered by the French chemist Paul-Émile Lecoq de Boisbaudran in 1875,
elemental gallium is a soft, silvery metal at standard temperature and pressure. ...
,
and solid
mercury.
References
External links
Tin cry on YouTubeMercury cry on YouTube
Tin
Materials degradation
Fracture mechanics
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