Activation energy for the reverse eutectoid reaction in hypo-eutectoid Cu–Al alloys

The values of the activation energy for the reverse eutectoid reaction (α + γ1) → β in the Cu–9 wt.%Al, Cu–10 wt.%Al and Cu–11 wt.%Al alloys were obtained using nonisothermal methods and considering two different reaction paths, one starting from annealed alloys and other from quenched alloys. The results showed that the activation energy for the reaction changes with Al concentration and strongly depends on the reaction path. The conversion dependence of the activation energy indicates a complex process comprising consecutive reactions which may be related with the dissolution of the pearlitic phase prior to the β phase formation.

► The reverse eutectoid reaction in Cu–Al alloys was studied using nonisothermal methods.
► The Cu–Al reverse eutectoid reaction is a complex process comprising consecutive reactions.
► Changes in the eutectoid reaction activation energy may be related to different reaction paths.