Nonisothermal Kinetics Study of Phase Evolution of Zn-Fe Intermetallics

Abstract

ABSTRACTThrough mechanical alloying of pure elemental powders of Fe and Zn, true homogeneous alloys of Γ (Fe3Zn10), Γ1 (Fe5Zn21), δ (FeZn7) and ζ (FeZn13) intermetallic phases are formed. Based on nonisothermal kinetics analyses, the highest activation energies associated with the metastable to stable transformations of these phases are determined as follows: 170±1 kJ/mol, 2 51±2 kJ/mol, 176±1 kJ/mol and 73 7±4 kJ/mol for the Γ, Γ1, δ and ζ-phases, respectively. These values reflect different diffusion/thermally induced processes associated with the transition of each of these phases.