Jominy test: a 100 mm long cylinder is heated above A<sub>3</sub> (austenitization) and quenched at one side by a water jet. The quenching vs to the distance to cooled side (thus vs the cooling speed) is evaluated by Rockwell hardness. The spherical prints on the flat (right) symbolize the marks of the Rockwell test
<a href="//commons.wikimedia.org/wiki/User:Cdang" title="User:Cdang">Cdang</a>
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<span class="int-own-work" lang="en">Own work</span>