Within the framework of the Fresnel–Kirchhoff theory, a computer simulation of the interaction of x-ray radiation with a wavelength of λ = 1.5374 Å (line CuK_α) with three-dimensional samples of arbitrary geometric shape made of alloys Fe–13%Cr–(2, 4, 6, 8)%Al and Fe–3%Cu–1%Ni at a temperature of 300 K, which are subjected to compression–tension deformation. The values of the relative deformation ε are equal to −0.10, −0.05, 0.00, 0.05, and 0.10. As shown, the x-ray radiation interacting with matter is very sensitive to changes in the electron density of the material. Based on known theoretical relations and the results of molecular-dynamic modelling, an approach of numerical calculations of refraction decrement δ and absorption coefficient β of x-ray radiation for multicomponent alloys with different percentage composition of chemical elements and different amount of deformation is proposed. The results of this work are applied in nature and can be useful both to developers of laboratory equipment and to specialists in the field of materials science.