Kinetic model of components interaction in Fe-Pb-O system

摘要

Under the conditions of the high temperature contact (650°C) of Armco-iron with oxygen containing lead (C_([O])=6 X 10~(-3)/10~(-6) mas.%) the following peculiarities of the components interaction in Fe-Pb-O system are determined: 1. lead never penetrates into pure iron; 2. lead penetrates only into iron-oxide by the way of reactionary diffusion; 3. latency period of iron oxidation in oxygen containing lead exists. Only binary oxide Fe_xO_y growths for this period and lead does not react with it; 4. after latency period lead penetrates into the iron-oxide by the way of reactionary diffusion. The possible mechanism of its interaction is solid-phase reaction between oxides: Fe_xO_y+[PbO] Fe_xO_yPb_z Fe_3O_4 + Pb + [O] + [vac] Fe_xO_y... At statement of reactionary diffusion problem for Fe-Pb-O system the boundary conditions of mass-exchange are formulated. These boundary conditions describe the non-stationary physical-chemical processes on interfaces adequately. It allows to make the predictions of solid-metal behavior in oxygen-containing lead more accurately.