Hot extrusion of aluminum powder at low reduction ratios: Analytical and metallographic studies
Tóm tắt
This paper deals with an investigation into the flow of aluminum powder billet during hot extrusion at low reduction ratios through square edge die under axisymmetric conditions. Analytical studies using the finite element method as well as the experimental observations are reported for various low reduction ratios ranging from 1.3:1 to 3.2:1 at extrusion temperatures, 300, 400, and 500 °C; friction effects have also been included. Extrusion pressures, velocity vectors, average pressure contours, and effective strain-rate contours are obtained using a velocity-pressure relationship. Analytical extrusion pressures agree quite well with experimental values. Metallographic investigations of the longitudinal section of partially extruded billets reveal very clearly the flow of the material in the different regions,viz., inside the container, near the die and the extruded portion, and are correlated with analytical results.
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