Need reason for that Ar3 ltemperature will always be lower than Ac3 or they can be equal under what conditions. what is effect of deformation on the same.
This terminology is used in metallurgy in the transformation of metal eutectics. Ac3 is the temperature at which the ferrite metal is COMPLETELY transformed into austenite by the heating process. The Ar3 is the temperature is when the austenite metal begins to cool down to revert to becoming ferrite again.
This difference between the heating and cooling varies with the rate of heating or cooling. The faster the heating, the higher the Ac point; the faster the cooling , the lower the Ar point. Also, the faster the heating and cooling rate, the greater the gap between the Ac and Ar points of the reversible (equilibrium) point A.