Theoretical Study of the Force Parameters of the ECAP-Linex Combined Process

The paper presents theoretical studies of a new deformation process combining the stages of equal-channel angular pressing (ECAP) and the Linex scheme. To analyse the resulting deformation forces, the stages of pressing in a matrix and compression by a chain conveyor are separately considered. Equations were provided for determining the forces acting on the drive pulley, ECA matrix, and chain element link. A trial calculation and comparative analysis with the previously known rolling-ECAP process showed that the new ECAP-Linex process allows for a stable deformation process with lower forces and a smaller channel junction angle in the matrix. The values obtained by equations are verified with computer simulation using the finite element method in the Deform program. A comparison of values showed that the force values in the calculation and simulation have a high level of convergence. For all three considered parameters, the difference value did not exceed 3%

Investigation of ECAP on Microstructure and Mechanical Properties of Bronze at Different Temperatures

Tin bronzes are widely used as structural materials in parts of friction units for critical applications operating in harsh operating conditions. In this work, the study of the influence of equal channel angular pressing on microstructure and mechanical properties of single-phase tin bronze is carried out. According to the analysis of the results of the study, it was revealed that the size of the grain is consistently refining with each new cycle of deformation. Moreover, analysis of the influence of deformation's beginning temperature on the evolution of microstructure and mechanical properties of single-phase tin bronze was conducted

Development and Computer Simulation of the New Combined Process for Producing a Rebar Profile

The study presents results of computer simulation by finite elements method of a new metal forming process combining the deformation of a billet with round cross-section on a radial-shear rolling mill and subsequent billet twisting in a forming die with a specific design. To analyze the efficiency of metal processing, the main parameters of the stress–strain state are considered: effective strain, effective stress, average hydrostatic pressure, and Lode–Nadai coefficient. The maximum value of effective strain up to 13.5 is achieved when a screw profile on the billet in the die is forming, which indicates an intensive refinement of the initial structure of the billet. During combined process, the nature of the deformation changes in the transverse direction from the axis of rotation to the surface. The central area of the billet is under the action of tensile stresses. In the peripheral part, compressive stresses grow. In the surface area, Lode–Nadai coefficient is 0.1 approximately, which indicates the high level of shear strain