KINETICS OF EUTECTOID TRANSFORMATION IN A CU-20.15 AT-PERCENT IN ALLOY

The growth kinetics of the product of the eutectoid transformation rea ction has been studied in a Cu-20.15 at.% In alloy in the temperature range 570 to 710 K. The Cu-In alloy was observed to undergo the eutect oid transformation into a lamellar structure consisting of alternate l amellae of alpha and delta phases. Pearlite was also observed to form into a granular morphology. Lattice parameter measurements indicated t hat the alpha phase has the composition corresponding to the equilibri um solvus. Analysis of the growth kinetics has indicated that the eute ctoid transformation in this system is controlled by interface diffusi on of solute at the alpha/beta interface.