Abstract

The review material reveals the question of the influence of impurities on the physical properties of alloys, as well as the influence of gases on processes in alloys. It has been established that the presence of hydrogen affects diffusion in alloys, and gases have a significant effect on the thermoelectromotive force of metals. The paper describes the addition of a third element to binary systems, which can expand or narrow the domain of existence of an ordered phase. The above examples of adding an impurity of vanadium or molybdenum to an alloy of iron and chromium increase the ordering temperature. It has been established that gases can have a significant effect on the thermoelectromotive force of metals and increase the hardness and reduce the ductility of metals, as well as cause their brittleness and delamination. It has been established that hydrogen (H2) in alloys (for example, Fe-Ni and Au-Cu) affects diffusion and atomic ordering processes. Also, a small concentration of hydrogen, as an impurity, can change the electrical resistance of alloys (for example, in a Pd-Au alloy). It has been established that the addition of a third element to binary systems can change the state diagram, which must be taken into account when solving problems for the production of heat treatment modes for alloys, determining the conditions for phase equilibrium, etc. The paper considers the dependence of hydrogen solubility on temperature in metals (Cu, Fe and Al) and establishes the dependence of hydrogen solubility in a metal on the concentration of impurity metals. The temperature dependence of hydrogen solubility in Fe-V alloys is also shown. The shift of the density of state is studied for different distributions of impurity atoms in the alloy in the order-disorder system, and the dependence of the density of states of disordered and ordered solid solutions is studied. The dependence of the relative solubility of atoms introduced into the pores of alloys with an fcc structure (of the Cu3Au type) is indicated, taking into account the solubility, on the parameter χ, which is proportional to the degree of long-range order in the octahedral and tetrahedral pores of the alloys. The dependence of the relative solubility of intercalated atoms in octahedral pores of alloys with a bcc structure (such as CuZn and Fe3Al) is considered. A plot of the dependence of the concentration of dissolved impurity atoms on the degree of order is shown for substitutional alloys with a bcc lattice, where the M2 coefficient is introduced, which does not depend on the degree of order. The effect of pressure as a measure of long-range order is also studied, where its step decreases or increases, or decreases and then increases and vice versa (order-disorder phase transition). An equally important result is the graphic dependence of solubility (c) on pressure (P) in disordered and ordered alloys.

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