Tech Talk
What is "Hardening"?
The process of increasing the surface hardness of a part. It is accomplished by heating a piece of steel to a temperature within or above its critical range and then cooling (or quenching) it rapidly. In any heat-treatment operation, the rate of heating is important. Heat flows from the exterior to the interior of steel at a definite rate. If the steel is heated to quickly, the outside becomes hotter than the inside, and the desired uniform structure cannot be obtained. If a piece is irregular in shape, a slow heating rate is essential to prevent warping and cracking. The heavier a section, the longer the heating time must be to achieve uniform results. Even after the correct temperature has been reached, the piece shouls be held at the temperature for a sufficient period of time to permit its thickest section to attain a uniform temperature. See "Workhardening".
