The process of forming graphite in cast iron is called the graphitization process. The basic process of the formation of cast iron structure is the formation of graphite in cast iron. Therefore, understanding the conditions and influencing factors of the graphitization process is very important to grasp the structure and performance of cast iron materials.

The first stage is the liquid phase hypoeutectic crystallization stage. Including, the primary graphite is directly crystallized from the liquid phase of the hypereutectic component, and the austenite and graphite are crystallized from the liquid phase of the eutectic component. Graphite.

The intermediate stage is the stage between eutectic transformation and sub-eutectoid transformation. Including secondary precipitation of austenite directly graphite and secondary cementite decomposition of graphite formed in this temperature range.

The third stage is the transformation phase of the analysis. Including the eutectoid graphite formed during the eutectoid transformation and the graphite formed by decomposition during annealing of eutectoid cementite.