Question

Difference between eutectoid and proeutectoid ferrite

Answer 1

The major difference between the microstructures of these two materials is eutectoid steel ends up with just pearlite whereas hypoeutectoid steel contains proeutectoid ferrite interspersed within the pearlite. Hence, proeutectoid ferrite exists as a standalone phase, but eutectoid ferrite is subsumed within pearlite (the other constituent of which is cementite).