1. To obtain a high case hardness it is necessary to reach, during carburizing, a saturation degree in excess of 2% C. Carburizing must be conducted at 950 or 100° C for 15 or 5 hrs. to obtain a total case depth of 1 to 1.2 mm, respectively. 2. The thickness of the layer with over 58 Rc depends then on the subsequent heat treatment. The best treatment at which the very hard layer is thickest consists of quenching from 1000°C, a cold treatment at −70°C and tempering at 160° C (or 500° C).
Read full abstract