Ostwald ripening of rod-shaped α-Fe particles in a Cu matrix

摘要

The coarsening behavior of rod-shaped α-Fe particles in Cu-1.0 wt.% Fe and Cu-1.0 wt.% Fe-1.2 wt.% Sb alloys during aging at 700℃ has been studied by transmission electron microscopy and electric resistivity. The kinetics of the decay of supersaturation with aging time t for both alloys coincide with the t~(-l/3) law. The coarsening kinetics of the cylindrical radius of the Fe particles obey the t~(1/3) law. Using the Lifshitz-Slyozov-Wagner theory modified for the case of rod-shaped particles by Speich and Oriani, the maximum value of the Cu/α-Fe interfacial energy γ and the volume diffusivity D of Fe in Cu for the Cu - Fe alloy are independently derived to be 1.3 J/m~2 and 3.9 x 10~(-16) m~2/s. Adding Sb to the Cu - Fe alloy decreases the values of γ and D.