Evaluation of the Possibility of Performing Cold Backward Extrusion of Axisymmetrical Thinwalled Aluminum Die Stampings with Square Section / Ocena Możliwości Wyciskania Przeciwbieżnego Na Zimno Osiowosymetrycznych Wyprasek Z Cienką Ścianką O Przekroju Kwadratowym Z Aluminium

Abstract

EvaluatIon of thE possIbIlIty of pErformIng cold backward ExtrusIon of axIsymmEtrIcal thInwallEd alumInum dIE stampIngs wIth squarE sEctIon Ocena mOżliwOści wyciskania przeciwbieżnegO na zimnO OsiOwOsymetrycznych wyprasek z cienką ścianką O przekrOju kwadratOwym z aluminiumThe paper presents evaluation of the possibility of performing cold backward extrusion of axisymmetrical thin-walled aluminum (Al 99.50, ENAW-1050A) die stampings with a square section at the strain ε=ln(A0/A1)=2 (where A0 -cross sectional area of the billet, A1 -cross sectional area of the die stamping), and the ratio h1/b=3.6 (where h1 -height of the die stamping in mm, b -width of the base of the die stamping in mm). The analysis was conducted on the basis of the results of computer modelling (FEM) and experimental investigations on backward extrusion. The boundary conditions for numerical calculations were determined experimentally with respect to the flow curve and mechanical properties of aluminum. The results of investigations into backward extrusion of thin-walled square-sectioned aluminum die stampings might be used as guidelines to develop a technological process for industrial practice.

The analysis of distributions of effective strain and flow stress in longitudinal sections of cold backward extruded copper cans for different punch-face shapes

“…QForm-2D/3D (Quantor-Form Ltd., Russia) uses the flow formulation for material behaviour. The estimation of the QForm simulation results was carried out in several works [21][22][23][24]. The analysis of these papers shows the good compatibility between the results of numerical simulation and experimental data.…”

Experimental Determination of Material Boundary Conditions for Computer Simulation of Sheet Metal Deep Drawing Processes

“…The papers also describe issues related to the input of data for modelling as material boundary conditions and some problems arising during the shaping of drawpieces and thin-walled products. The results of some of them [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] are discussed below.…”

Influence of elongation factor on distributions of effective strain and flow stress for pushing through a conical die process of round bars made from S355 steel

“…Drawing, forging with the use of swaging machines and cross rolling are employed while manufacturing stepped parts or reducing the cross section of the shafts and round bars in industrial practice [1][2][3][4]. In the 1970s, Marciniak Z. and Kopacz Z. developed a cold rolling method which allowed forming cylindrical gears, involute splines and other circular profiles in Poland [5]. The most essential features of the WPM method, distinguishing it from other known methods, involve the use of two circular segments as tools and adoption of kinematics that allows one-directional rolling with a symmetrical system of forces relative to the axis of the rolled material.…”

“…In the case when the jaws with internal smooth rolling surfaces are used as tools, it is possible to reduce the cross section of the shafts and tubes. The maximum initial diameter of shaft from medium steel to be reduced is 30 mm [5]. Relatively new manufacturing technologies of stepped parts are cross-wedge rolling and rolling-extrusion forming process [6].…”

“…Deformation ratios of the material for drawing process and pushing it through a die process in industrial practice is determined by elongation factor λ. It is given by formula [1,3,5,7]…”