Description
A salt bath for tempering structural parts made of iron and steel treated in a cyanide-free or low-cyanide nitriding salt bath or other cyanide-containing salt bath.
This process is also useful if the construction part has previously been treated in cyanide containing salt baths, such as in carburization. The cyanide-containing salt that adheres to the surface of the build-up and is drawn into the heat bath is thus destroyed by oxidation so that the wash water used later is cyanide-free. The cyanide content in salt baths used for austenitization or carburization is limited to about 10% by weight (calculated as NaCN) because at high cyanide contents the salt containing cyanide and nitrate containing salt heating bath- An unusually violent reaction can occur between nitrates.
