Case-hardened steel. Light micrograph of a section through a case-hardened steel tool. The brown area (right) is the original low-carbon (soft) steel,

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Case-hardened steel. Light micrograph of a section through a case-hardened steel tool. The brown area (right) is the original low-carbon (soft) steel, the orange area (left) is case-hardened. Case-har- dening is performed when soft steel has been used to manufacture a tool, which allows easy finishing of the piece. In order to harden the surface, the tool is either heated near a source of carbon or dipped into liquid sodium cyanide. Carbon atoms dissolve through the metal, altering its crystal structure and increasing mechanical strength. Magnification unknown.

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Size: 5126px × 3496px
Photo credit: © ASTRID & HANNS-FRIEDER MICHLER/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: case, chemical, chemistry, compound, compounds, harden, hardened, hardening, materials, science, steel