Patent ID: 6453536
Filing Date: 2002-09-24
Classification: B21C,Y10T

Abstract:
Method of producing hollow profiles having small external diameters and/or small wall thickness from a nickel titanium alloy by shaping a composite block, whereinin a first step, a composite block is formed comprising a solid core of nickel titanium alloy, a first hollow block of nickel titanium alloy surrounding the core, and a separating layer disposed between the first hollow block and the core, in a second step, the composite block is shaped by a formation method, and in a third step, the first hollow block shaped into a first hollow profile, and the shaped core are removed from the shaped composite block, characterized in that either the composite block is formed with one or more additional hollow blocks which are placed around the first hollow block and which each comprise a separating layer between neighboring hollow blocks and, in the second step, the composite block comprising several hollow blocks and the core is shaped, or, following the second and before the third step, the shaped first composite block is inserted as a core into an additional hollow block of a nickel titanium alloy, wherein the second composite block formed in this fashion comprises a separating layer between the core and the additional hollow block, and, subsequently, the second composite block is shaped by a formation method, and, subsequently, in the third step, the additional hollow block, shaped into a hollow profile, the additional shaped first composite block and the additional shaped core are removed from the shaped second composite block.