Abstract: Very fine grain metal billets are produced by loading alloy metal powder of desired composition into a metal extrusion container in successive layers of two or four inches deep. Each layer after loading is compacted by a high energy rate forming ram so as to introduce energy on the order of 3.times.10.sup.6 psi per layer and at least 18.times.10.sup.6 psi total. An inner plate is then loosely placed on the compacted powder. On top of the inner plate is placed a cover plate which is welded to the container. The filled container is then heated in a furnace to an extrusion temperature below the melting point of the alloy and is extruded in an extrusion press having a ratio of about 3:1 with a force of about 3,000 tons. The inner plate does not move at the same rate as the container and in effect is partially extruded against the powder so as to raise the density of the extruded billet to substantially 100% of its theoretical density.

Abstract: Metal powder of the desired composition having a particle size of -80 mesh is charged into an extrusion container, preferably a piece of carbon steel pipe, in successive layers about two inches thick. Each layer is compacted after deposition by a high energy rate forming ram so as to raise the tap density of the powder to about 80% of theoretical. An inner cover plate is then placed loosely on the compacted powder in the extrusion container, and is not attached to the container shell. On top of this inner plate is placed an outer cover plate which is welded to the container shell. Both plates are also of carbon steel, but are much thicker than the container wall. The container so prepared is heated in a heating furnace to a temperature below the melting temperature of the container and the powder alloy thus raising the density of the powder to about 90-93% of theoretical.