Method for producing a hard metal stock

Abstract

The invention relates to a process for producing a hard metal batch by drying a wet slurry - 3 - which is produced by wet-milling the hard material and binder metal fractions desired in the finished batch to the desired grain size, using water as liquid phase. According to the invention, the wet slurry - 3 - is applied to a moving carrier belt - 1 - with a solids content of from 75% by weight to 95% by weight and in a layer thickness of from 0.2 mm to 2 mm. As it passes through a drying zone - 4 -, the wet slurry - 3 - is heated, over the course of in total from 1 minute to 7 minutes, to a maximum temperature in the range from more than 100° C. to 150° C. The time which it takes for the wet slurry - 3 - to be heated to more than 100° C. is in a range from 15 seconds to 2 minutes. The hard metal batch which has been dried in this manner is then cooled to room temperature and if necessary comminuted.

1 - 5 . (canceled)  
   
   
       6 . A process for producing a hard metal batch, which comprises the following steps: 
 providing a wet slurry with a solids content of from 75% by weight to 95% by weight and water as a liquid phase;    depositing the slurry on a moving carrier belt at a layer thickness of from 0.2 mm to 2 mm;    passing the slurry through a drying zone and heating the slurry in the drying zone, for a time period of between 1 minute and 7 minutes, to a maximum temperature within a range from >100° C. to 150° C., wherein a time period during which the slurry is heated to over 100° C. is within a range from 15 seconds to 2 minutes, to form a dried hard metal batch; and    cooling the hard metal batch to room temperature and, optionally, comminuting the hard metal batch.    
   
   
       7 . The process according to  claim 6 , which comprises forming the wet slurry by wet-milling hard material and binder metal fractions to a desired grain size, and optionally adding fractions of a pressing aid.  
   
   
       8 . The process according to  claim 6 , which comprises depositing the wet slurry in a layer thickness of from 0.5 mm to 1.0 mm.  
   
   
       9 . The process according to  claim 8 , which comprises passing through the drying zone within a total time period of from 1.5 minutes to 6 minutes, setting the maximum temperature to 120° C., and heating the wet slurry to over 100° C. within a time range from 30 seconds to 60 seconds.  
   
   
       10 . The process according to  claim 6 , which comprises first heating the wet slurry to a desired temperature by hot air and subsequently heating by way of additional radiant heat.  
   
   
       11 . The process according to  claim 10 , which comprises generating the radiant heat by infrared radiators.