Modeling the Microstructure Evolution During the Combined Process of Drawing With Cryogenic Cooling

In this study, finite-element modeling of the microstructure evolution of the combined drawing process with cryogenic cooling by JMAK and Cellular Automata methods was carried out. The use of different methods is due to the fundamental difference in the results obtained—in the JMAK method, it is possible to obtain only grain size data, but this is calculated for the entire workpiece volume. In the Cellular Automata method, the calculation is performed only at predefined points, but in this case the user receives information about the size and shape of the grains. An analysis of the initial microstructure of 25 µm showed that the most optimal option is a reduced drawing speed and the absence of intermediate heating—in both considered blanks, a grain size of 0.5 µm approximately was obtained on the surface. At the same time, variants with an increased deformation rate also have fairly good grain-grinding results up to 0.7 µm. At the same time, it was found that the use of intermediate heating to ambient temperature in the proposed thermomechanical processing scheme will lead to a higher grain size gradient along the wire section.