Upper bound estimate of the power parameters of transverse-corner extrusion

Abstract

Aliiev I., Levchenko V., Chuchin O., Kartamyshev D., Kotsiubivska K. Upper bound estimate of the power parameters of transverse-corner extrusion

The article considers the process of combined transverse-corner extrusion of a ledge at an angle in a die with a conical zone. Simulating of the force mode of the combined extrusion process was performed by the upper bound estimate method using kinematic modules, which made it possible to independently evaluate the effect of geometric parameters on the reduced deformation pressure. The possibility of supplementing the reduced pressures when sequential combining extrusion schemes was also confirmed. It has been determined that the choice of the calculation scheme and the analysis of the process must be carried out depending on the relative height of the deformation zone. Calculation formulas for plane transverse extrusion obtained by the upper bound estimate method show close results to experimental data and to similar solutions for other problems of plane deformation in the processes of restamping and upsetting, which differ in the form of the velocity field and friction conditions at the boundaries. Dependences for the deformation pressure during corner extrusion in a die with an inclined generatrix were obtained using a triangular modulus, for which a method for calculating the pressure components on the velocity discontinuity lines is described. Graphical analysis of the reduced pressure dependence found that the parameter that has the greatest influence on the pressure level is the relative thickness of the process h/s, which characterizes the degree of metal reduction. Recommendations for calculating the power parameters of transverse-corner extrusion can be used in the design of extrusion processes both for parts with ledges and hollow conical products.