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This paper concerns the application of variational methods for the formulation of object motion equations as well as generation heat and its transfer formulated in the updated Lagrange description. These physical phenomena occur in the processing of metals in which there are thermal, plastic viscous and phase deformations. The obtained incremental variation equation of the object's motion and the incremental variation of the heat conduction equation were discretized by the Finite Element Method to obtain discrete systems of equations. These equations are solved by known methods for given boundary and initial conditions. As a result, a column vector of the displacement increment and a column vector of the temperature increment in the object nodes are obtained at each time step. Examples of the use of these methods for the burnishing rolling process with electric current are shown. [ABSTRACT FROM AUTHOR]

This article concerns the application of topological optimization with numerical methods in the ABAQUS system of machine parts on the example of a laser cutter gate. The gate structure was optimized with the initial mass of 566 kg, assuming that the gate deflection is less than the permissible displacements and the reduced stress are lower than the allowable stresses. It has been shown that the optimal construction of the gate has a mass of 28.1 kg. In addition, the new gate can be made from one sheet of sheet metal using a simple laser cutting method. [ABSTRACT FROM AUTHOR]

The paper presents the innovative process with possibility of predict the state of deformation and stresses in a two-stage metal forming process. In the first stage, regular surface roughness with arched outlines are embossed. In the second stage, these inequalities are flat burnished to obtain the required dimensions, roughness of the surface, and state of deformation and stresses in the surface layer of the workpiece. The process are considered as a geometrical and physical non-linear boundary and initial value problem, with unknown boundary conditions in the contact zone. The applications were developed in the Ansys/LS-Dyna system, which makes possible a complex time analysis of the states of displacements, strains and stresses, in the workpiece in the two-stage cold metal forming processes. Application of this method were showed for examples the modelling and the analysis of the regular asperities with arched outlines. In the simulations, the material as well as the geometrical parameters of surface asperities were changed. The simulation results were verified experimentally. [ABSTRACT FROM AUTHOR]

The paper presents the results of computer modelling using FEA and experimental researches of the influence of technological parameters of burnishing rolling process on resistance to fatigue wear of shafts. For solution of elaborate equation of motion the explicit method was used. This allows to carries out the time analysis of the displacements, strains and stresses state’s in workpieces. In addition, the numerical analyses for the fatigue wear component after burnishing for low frequency loads were carried out. The results of the numerical analysis were experimentally verified by researching the surface layer after burnishing. In addition the shafts on fatigue wear were tested. [ABSTRACT FROM AUTHOR]

The shearing process such as the blanking of sheet metals has been used often to prepare workpieces for subsequent forming operations. The use of FEM simulation is increasing for investigation and optimizing the blanking process. In the current literature a blanking FEM simulations for the limited capability and large computational cost of the three dimensional (3D) analysis has been largely limited to two dimensional (2D) plane axis-symmetry problems. However, a significant progress in modelling which takes into account the influence of real material (e.g. microstructure of the material), physical and technological conditions can be obtained by using 3D numerical analysis methods in this area. The objective of this paper is to present 3D finite element analysis of the ductile fracture, strain distribution and stress in blanking process with the assumption geometrical and physical nonlinearities. The physical, mathematical and computer model of the process are elaborated. Dynamic effects, mechanical coupling, constitutive damage law and contact friction are taken into account. The application in ANSYS/LS-DYNA program is elaborated. The effect of the main process parameter a blanking clearance on the deformation of 1018 steel and quality of the blank’s sheared edge is analyzed. The results of computer simulations can be used to forecasting quality of the final parts optimization. [ABSTRACT FROM AUTHOR]

The paper presents the results of experimental researches and numerical simulations of the duplex burnishing process. During duplex burnishing process the treatment is carry out in two stages. In the first stage - on the semi-fabrication surface, the regular asperities are embossed with triangular, symmetrical, periodic outline. In the second stage the asperities are burnished (smooth burnishing) till the needed asperities equalized, resulting in a smooth and strengthened surface layer. The implementation of such technology results in receiving of a new surface layer characterized by favorable functional properties, particularly increased resistance to fatigue wear. [ABSTRACT FROM AUTHOR]

The aim of this article is to demonstrate the possibility of using burnishing rolling process as the technology of product development. The experimental researches were carried out, showing the ability to form the surface layer of the product with the desired properties. First, during turning rolling the surfaces of the samples were prepared. Then, the surfaces were burnished. The influence of turning process on the state of the surface layer parameters of C45 steel shafts are shown. Among the examined aspects the surface roughness, nano-roughness, material bearing, surface microstructure, metallographic structure were considered. Numerical simulation were conducted. Conclusions from the experiments and simulation were given. [ABSTRACT FROM AUTHOR]

For the experiment needs, the own experiment plan was developed. The researches were carried out to determine the effect of variable, small feed on the chip’s shape. To provide orthogonal free cutting special specimens were prepared. Obtained chips were divided according to shapes and also scanned using a scanning electron microscope (SEM). Conclusions from the experiments were given. [ABSTRACT FROM AUTHOR]