Method of fabricating compacted powdered metal extrusion billets

Claim 1

IN THE FORMATION OF COMPOSITE MULTI-METAL EXTRUSION BILLETS FOR THE HIGH YEILD EXTRUSION OF SELECTIVELY CLAD METAL PRODUCTS, THE STEPS OF POSITIONING AN ELONGATE, HOLLOW OPEN-ENDED AND RELATIVELY THIN-WALLED CORE MEMBER OF A FIRST PREDETERMINED CONFIGURATION WITHIN A CLOSED-END DEFOMABLE OUTER SHELL MEMBER OF LARGER TRANSVERSE DIMENSION AND OF SUBSTANTIALLY COMMENSURATE LENGTH THEREWITH WITH ONE OPEN END OF SAID CORE MEMBER DISPOSED IN ABUTTING RELATION WITH THE CLOSED-END DEFINING WALL PORTION OF SAID SHELL MEMBER TO DEFINE A PLURALITY OF POWDERED METAL RECEIVING CAVITIES THEREIN, INTRODUCING A FIRST FINELY DIVIDED CLADDING METAL POWDER MATERIAL HAVING A PREDETERMINED ANGLE OF REPOSE INTO THE CAVITY DEFINED BY AND DISPOSED INTERMEDIATE SAID CORE MEMBER AND SAID SHELL MEMBER IN SUFFICIENT QUANTITY TO AT LEAST PARTIALLY FILL SAID CAVITY, AXIALLY DISPLACING SAID CORE MEMBER TO POSITION SAID OPEN END THEREOF IN PREDETERMINED SPACED RELATION WITH THE CLOSED END DEFINING WALL PORTION OF SAID SHELL MEMBER TO PERMIT SAID PREVIOUSLY INTORDUCED CLADDING A POWDER TO FLOW INTO THE CORE CAVITY AND TO THERE ASSUME A GENERALLY CONICAL END CAP CONFIGURATION AS DETERMINED BY ITS ANGLE OF REPOSE, INTORDUCING A SECOND FINELY DIVIDED CORE METAL POWDER MATERIAL OF METALLURGICAL CHARACTERISTICS DIFFERENT FROM THOSE OF SAID FRIST POWDER MATERIAL INTO A CAVITY DISPOSED WITHIN AND DEFINED BY SAID HOLLOW CORE MEMBER AND CONCIAL END CAP CONFIGURATION IN SUFFICIENT QUANTITY TO AT LEAST PARTIALLY FILL SAID CAVITY, AXIALLY REMOVING SAID CORE MEMBER FROM SAID SHELL MEMBER TO INTRODUCE THE PARTICLES OF SAID FIRST AND SECOND METAL POWDERS DISPOSED IN ABUTTING RELATION WITH THE INNER AND OUTER SURFACES OF SAID CORE MEMBER INTO INTIMATE INTERFACIALLY ENGAGED RELATION, SEALING SAID DEFORMABLE SHELL MEMBER, AND ISOSTATICALLY SUBJECTING SAID SEALED DEFORMABLE SHELL MEMBER AND ITS CONTENTS TO HYDROSTATIC PRESSURE TO COMPACT SAID POWDERED METAL CONTENTS THEREOF TO A PREDETERMINED DESIRED DENSITY WITHOUT APPRECIABLE CHANGE IN THE RELATIVE PHYSICAL POSITIONAL DISPOSITION OF SAID FIRST METAL MATERIAL TO SAID SECOND METAL MATERIAL.