The quenching time and holding time of quenching and tempering treatment are basically the same as austempering, that is, the heating temperature is 860-920℃. In order to avoid cracking during quenching and cooling, oil cooling is generally used except for simple castings with water cooling. The structure after quenching is flake martensite and spherical graphite. Then heat to 550-600°C and temper for 2-6 hours.
Ductile cast iron can be subjected to a variety of heat treatments, such as QT400 can be annealed, QT700 can be normalized and tempered, but it is best to perform normalizing treatment before induction heating surface quenching. The details of the heat treatment of ductile cast iron are like this. If you have more questions, please come to consult.