Gatsenko T. The regular dependencies for diffusion processes on moving grain boundaries of copper-titanium alloys

The thesis is devoted to investigation of kinetic and thermodynamic parameters of cellular precipitation of supersaturated solid solutions for the whole range of homogeneous supersaturated solid solutions of titanium in copper, influence of alloying with the third element on the rate of the cellular precipitation and effect of cyclic heat treatment of "cellular precipitation - continuous dissolution" model on the grain structure of the alloy. The parameters of cell nucleation kinetics,migration rate of the cellular reaction front, the interlamellar distance, the lattice parameters of quenched alloys and stripped solid solution, cell concentration and thermodynamic parameters were determined. The effect of micro-alloying with the third element on the rate of cellular precipitation in the copper alloy with 5.69at.% titanium at the temperature of 873K was investigated and, it was shown, that nickel and indium accelerate the cellular precipitation, while the others hinder it. It was found, that the initial grain size in Cu-5.69 at.% Ti alloy was milled more than 90 times by 6 iterations of cyclic heat treatment in the form of "cellular precipitation - continuous dissolution" model.