Under equilibrium conditions, pro-eutectoid ferrite will form in iron-carbon alloys containing up to 0.8 wt% carbon. The reaction occurs at 910 C in pure iron, but takes place between 910 C and 723 C ...

The eutectoid phase transition in the iron carbon system takes place at 727 C. The three components in equilibrium at this temperature are Austenite, g, with the composition Fe - 0.77 wt % C, Ferrite, ...

3.14a), and rely on diffusion. Pearlite nuclei occur on austenite grain boundaries, but it is clear that they can also be associated with both pro-eutectoid ferrite and cementite. In commercial steels ...