Method of producing dense metal tubes or the like
AssigneeGranges Nyby AB
InventorChrister Aslund
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Abstract
A method and a capsule and a blank for producing tubes, bars or similar profiled elongated dense metal objects, preferably in stainless steel qualities, by single or multi-stage extrusion of capsules which are filled with powder of metals or metal alloys or mixtures thereof or with mixtures of powder of metals and/or metal alloys with ceramic powder and sealed and which are adapted in their form to the desired object or intermediate product, as starting material a powder being used which consists at least predominantly of substantially spherical grains and the capsule filled with said powder and sealed being compressed by means of cold-isostatic pressure acting all round until the density of the powder reaches at least 80% of the theoretical density.
Claims17
In a method for producing an elongated dense metal object in which metal powder is sealed in a metal container, the metal container with the metal powder therein is partially compressed in a first compression step and the partially compressed metal container so formed is extruded at elevated temperature in a second compression step, the improvement wherein (1) the metal particles of said metal powder are substantially spherical, (2) said container is formed from a ductile metal, (3) the wall thickness of said container is at most 5% of the outer diameter of said container, (4) said metal contaner is subjected to cold-isostatic pressure acting on all surfaces of said container during said first compression step, and (5) said metal container is compressed until the density of the metal powder therein reaches at least 80% of the theoretical density during said first compression step.
Dependencies are inferred from the claim text.