Theoretical Study of Particle Dissolution during Homogenization in Cu-Fe-P Alloy

The effect of temperature, soaking time and particle size on the dissolution of particles (Fe3P and Fe) during homogenization was simulated employing Thermocalc (R) and DICTRA software. The initial precipitate size was determined through metallographic evaluation on industrial as-cast Cu-Fe-P alloy. The particle sizes vary from submicron (< 1 mu m) up to 10 mu m before the heat treatment. As homogenization temperature rises, the dissolution rate increases as well, but only on temperatures above 1273 K (1000 degrees C) is the rate capable of completely dissolving particles effectively. At temperatures above 1273 K (1000 degrees C), precipitates with sizes below 5 mu m dissolve completely into the Cu matrix, while larger particles only slightly decrease their size. Particles at enriched copper areas remain undissolved and slightly increase their size which is attributed to micro segregation and the local change of equilibrium conditions. The simulation results are in agreement with homogenization trials at lab scale.