Tin cry

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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 in the metal.[1] 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 231.9 °C (449.4 °F; 505.0 K) - 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[citation needed], indium[2], zinc[citation needed], cadmium[3], gallium[citation needed], and mercury[4]

References[edit]

  1. ^ "Video of the demonstration". University of Cambridge. Archived from the original on 23 February 2014. Retrieved 15 February 2021.
  2. ^ "LibreTexts, Chemistry, Chemistry of Indium".
  3. ^ "LibreTexts, Chemistry, Chemistry of Cadmium".
  4. ^ Reeder, Cody (17 Mar 2015). Bending Solid Mercury: It Cries!. Retrieved 3 December 2021.

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