Apparatus for the continuous extrusion of solid articles

Apparatus capable of the continuous extrusion manufacture of a solid composite porous article from a substantially uniform particulate mixture of a quantity of particles of a binder material and a quantity of particles of a primary material, said primary material having a substantially higher softening temperature than a softening temperature of said binder material, which comprises:

• an extruder barrel housing an extrusion screw, said extruder barrel having a feed inlet and feed outlet;
• an elongated, smooth extrusion die attached to the feed outlet of the extruder barrel, said die defining a cavity having an inlet end, an extrusion end, and a substantially uniform cross-section, which cross-section is not substantially smaller than the cross-section of an inside diameter of the extruder barrel;
• means for forcibly injecting said particulate mixture into the inlet end of said die cavity;
• means in said die adjacent to the inlet end thereof for heating said particulate mixture within said die cavity to a temperature substantially above the softening temperature of said binder material but less than the softening temperature of said primary material;
• means external of said die cavity for continuously providing controlled pressure of between about 5 to about 400 psi to said heated particulate mixture within the die cavity during extrusion of the particulate mixture;
• and
• means in said die adjacent the extrusion end thereof for rapidly cooling said particulate mixture within the die cavity to below the softening temperature of the binder material to form a monolithic solid composite material whereby said substantially uniform particulate mixture is deformed, consolidated into a desired form and solidified in the extrusion die and is extruded from said die cavity as a solid composite porous article.