Carbide mandrel for micro extrusion of metals

A carbide mandrel assembly mountable in an extrusion die apparatus having an extrusion die which has an extrusion die aperture, said carbide mandrel assembly comprising:

• a retainer collar mountable to said extrusion die apparatus, said retainer collar having a rectangularly-shaped longitudinal slot extending therethrough, said rectangularly-shaped longitudinal slot facing said extrusion die aperture and substantially parallel thereto;
• a carbide mandrel having a rectangularly-shaped holder portion and a mandrel portion, said rectangularly-shaped holder portion being received within said rectangularly-shaped longitudinal slot of said retainer collar and said mandrel portion having at least one mandrel element which extends into said extrusion die aperture;
• and
• longitudinal gruide means for retaining said rectangularly-shaped holder portion of said carbide mandrel in said rectangularly-shaped longitudinal slot of said retainer collar, said longitudinal guide means having a non-planar contoured cross-section.

An extrusion die apparatus comprising:

• a backer plate having a centrally disposed first clearance aperture;
• a die holder mounted to said backer plate, said die holder having a second clearance aperture aligned with said first clearance aperture, and an aligned die cavity;
• a die having a die aperture mounted in said die cavity with said die aperture aligned with said first and second clearance apertures;
• a housing attached to said backer plate, said housing having a feed chamber passing therethrough circumscribing said die aperture and a bridge portion spatially separated from said die, said bridge portion spanning said feed chamber and having a retainer cavity provided therein facing said die aperture;
• a retainer collar mounted within said retainer cavity, said retainer collar having a longitudinally-disposed mandrel slot facing said die;
• means for securing said retainer collar in said retainer cavity;
• a carbide mandrel received within said longitudinally-disposed mandrel slot, said carbide mandrel having at least one mandrel element which extends into said die aperture when said carbide mandrel is received in said longitudinally-disposed mandrel slot and said retainer collar is mounted in said retainer cavity;
• and
• longitudinal guideway means for retaining said carbide mandrel in said longitudinally-disposed mandrel slot, said longitudinal guideway means having a non-planar contoured cross-section.