• The features of recrystallization of steels under laser action

    Materials Science. Non-Equilibrium Phase Transformations., Vol. 8 (2022), Issue 1, pg(s) 7-9

    The features of recrystallization of steels with different chemical composition and type of crystal lattice under laser action were investigated. These processes are of great importance in high-speed laser heating and cooling, as well as in the formation of the microstructure of steels under the influence of residual heat.
    It was found that recrystallization under laser action has signs of a dynamic process due to an increase in the dislocation density. In addition, the dislocation substructure of steel is inherited from the initial hot-deformed state. It is shown that the mechanism of laser recrystallization depends on the type of steel, chemical composition, and crystal lattice.
    In different steels, the development of primary, collective, and secondary recrystallization was observed. In this case, the change in the grain structure of steels took place against the background of an increased density of dislocations and the formation of a cellular dislocation substructure.

  • Calculating contouring tool by finite difference method

    Machines. Technologies. Materials., Vol. 13 (2019), Issue 1, pg(s) 36-40

    During the radial deformation of contouring tool, its active diameter is getting smaller than the initial one, and the cutting depth is becoming lower than planned. Thus, the diametrical size of the machined hole is always smaller than contouring tool, by value of the elastic radial deformation. In this regard, in the manufacture of contouring tool, it is necessary to make appropriate adjustments in the diametrical size of its cutting edge, depending on its elastic radial deformation.
    The paper dwells on the thermo-elastic problem of calculating contouring tool for the purpose of determining the actuating diametrical size of its cutting edge, and for determining the area of the application of tool material. Solving of non-dimensional non-stationary problem is carried out by method of finite differences. At each time step, the system of algebraic equations is solved by iterative method.
    There have been obtained the results for the temperature field and displacement components.


    Machines. Technologies. Materials., Vol. 10 (2016), Issue 6, pg(s) 36-37

    The article is devoted to the calculation and verification of the shredding chamber of a two-shaft shredder for crushing of concrete, rubber, plastic and wood. In this work a model study of the shredding chamber of such type of shredder has been done. The studies of the mechanical load and behavior of the shredding chamber have been conducted through solving the equations describing the mechanical processes under operating conditions by the finite element method. For this purpose, a three-dimensional geometric model of the bottom of the chamber has been generated, which is discretized to a planned network of finite elements in the programming environment of ANSYS MECHANICAL APDL.