Method for the manufacture of a shaped body as well as green compact

Abstract

A method for manufacturing a shaped body, comprising creating a mixture of a metal powder and binding agent, compacting the mixture to form a green compact, heating the green compact to a debinding start temperature T 1 , debinding the green compact by controlled heating of the green compact from start temperature T 1 to end temperature T 2 at a heat-up rate R 1 , presintering the debindered green compact to the presinter end temperature T VS at a heat-up rate R HVS , cooling the green compact from the presinter end temperature T VS at a cool-down rate R KVS , whereby at least the heat-up rate R HVS , the presinter end temperature T VS , and the cool-down rate R KVS are tuned relative to each other in such a way that the presintered green compact forming a blank has a surface porosity of 16% to 22% after presintering, and machining and sintering of the blank to form the shaped body.

What is claimed is: 
     
         1 . A green compact for the manufacture of a dental prosthesis, or a part thereof, the green compact comprising:
 a presintered green compact of a dental metal alloy having a surface porosity of from 16% to 22%.   
     
     
         2 . The green compact according to  claim 1 , wherein the surface porosity is from 18% to 20%. 
     
     
         3 . The green compact according to  claim 1 , wherein the dental metal alloy is a nickel-chromium alloy consisting of:
 Nickel: 50 to 70% by weight;   Chromium: 20 to 35% by weight;   Molybdenum: 0 to 10% by weight;   Tungsten: 0 to 20% by weight;   Other elements: less than 10% by weight; and   wherein a sum total of the elements adds up to 100% by weight.   
     
     
         4 . The green compact according to  claim 1 , wherein the dental metal alloy is a cobalt-chromium alloy consisting of:
 Cobalt: 50 to 70% by weight;   Chromium: 20 to 35% by weight;   Molybdenum: 0 to 10% by weight;   Tungsten: 0 to 20% by weight;   other elements: less than 10% by weight; and   wherein a sum total of the elements adds up to 100% by weight.