Experiments in extrusion, Part 2 - the hot extrusion of beryllium.

Abstract

A technique for the hot extrusion of beryllium powder within a mild steel sheath has been developed. Limitations exist with this technique in the control of extruded dimensions, particularly on complex sections or where the sheath thickness is greater than about 0.020 inch. The use of pre-consolidated powder billets is recommended to reduce the danger of the sheath buckling or splitting during extrusion and to improve the surface finish and dimensions of the product. Pick-up of oxygen and nitrogen by the beryllium was observed where the beryllium was not completely sealed from the atmosphere during heating and extrusion. This factor affected the mechanical properties of the material, particularly hardness. The mechanical properties of the sections were determined as a function of extrusion conditions; these properties are sensitive to the choice of extrusion temperature, presumably reflecting a tendency for residual work hardening to increase at the lower extrusion temperatures