Powder-metallurgical steel

Abstract

The invention relates to a method for producing powder-metallurgical steel. Said method consists of the following steps: a steel powder, preferably having a predetermined structure, is produced; the steel powder is mixed with a binding agent to form a plastically deformable raw material; the raw material is initially shaped to form a blank having a predefined spatial form; and the blank is sintered.

1 . A method for producing a powder-metallurgical steel, particularly a tool steel, such as HSS or HSS-E steel, having the following process steps:
 producing steel powder have a predetermined microstructure;   mixing the steel powder with a binding agent to form a plastically deformable raw mixture;   preforming the raw mixture to form a blank having a predefined spatial form; and   sintering the blank.   
     
     
         2 . The method according to  claim 1 , characterized in that the steel powder undergoes processing to homogenize the geometry of the powder particles while it is being mixed with the binding agent. 
     
     
         3 . The method according to  claim 1 , characterized in that the steel powder undergoes processing to homogenize the geometry of the powder particles before it is mixed with the binding agent. 
     
     
         4 . The method according to  claim 3 , characterized in that the steel powder undergoes a selection process before mixing so that it has a predetermined particle size and/or particle size distribution when it undergoes the mixing process. 
     
     
         5 . The method according to  claim 1 , characterized in that the steel powder is obtained by grinding or crushing steel particles. 
     
     
         6 . The method according to  claim 1 , characterized in that the steel powder is mixed with a binding agent, for example cobalt. 
     
     
         7 . The method according to  claim 1 , characterized in that the blank undergoes a hot isostatic pressing (HIP) process before, during or after sintering. 
     
     
         8 . The method according to  claim 1 , characterized in that the blank undergoes a thermal treatment, for example a hardening process, during the sintering process to control the steel microstructure. 
     
     
         9 . The method according to  claim 1 , characterized in that the plastically deformable mass undergoes a preferably continuous extrusion process, wherein the plastically deformable mass is extruded through an extrusion die with a nozzle ( 102 ) to form a continuous rod. 
     
     
         10 . The method according to  claim 9 , wherein at least sections of an interior channel are arranged for transporting coolant and/or lubricant into the rod. 
     
     
         11 . The method according to  claim 10 , wherein at least sections of the interior channel are constructed in the form of a coil or as straight sections. 
     
     
         12 . A raw mixture for manufacturing a powder-metallurgical steel, particularly a tool steel such as HSS or HSS-E steel, comprising:
 steel powder having a predetermined microstructure; and   binding agent mixed therewith in such manner that the raw mixture is suitable for extruding and subsequent sintering.   
     
     
         13 . A powder-metallurgical steel for manufacturing a tool, wherein the steel is producible by a method according to  claim 1 . 
     
     
         14 . The steel according to  claim 13 , wherein the steel is producible from a raw mixture comprising steel powder having a predetermined microstructure and binding agent mixed therewith in such manner that the raw mixture is suitable for extruding and subsequent sintering. 
     
     
         15 . A component or semifinished product manufactured according to the method according to  claim 1  or from a raw mixture comprising steel powder having a predetermined microstructure and binding agent mixed therewith in such manner that the raw mixture is suitable for extruding and subsequent sintering or from a steel producible by (1) producing steel powder have a predetermined microstructure; (2) mixing the steel powder with a binding agent to form a plastically deformable raw mixture; (3) preforming the raw mixture to form a blank having a predefined spatial form; and (4) sintering the blank.