Method for producing a moulded body from sintered steel

Abstract

The invention relates to a method for producing a molded body made of sintered steel, with a sintering powder on the basis of iron being mixed with a master alloy powder containing nickel, boron and iron, and with the powder mixture being pressed into a formed body before the formed body is sintered under the conditions of a liquid-phase sintering with a volume share of liquid phase up to 15%. In order to improve the impact strength, it is proposed that the boron content of the powder mixture is between 0.03% and 0.2% by weight at a boron share of the master alloy powder of less than 10% by weight, that the weight ratio between the nickel and the boron share of the powder mixture exceeds 5 and that the master alloy powder has an average particle size of between 10 and 90 μm.

1 . A method for producing a molded body made of sintered steel, with a sintering powder on the basis of iron being mixed with a master alloy powder containing nickel, boron and iron, and with the powder mixture being pressed into a formed body before the formed body is sintered under the conditions of a liquid-phase sintering with a volume share of liquid phase up to 15%, wherein the boron content of the powder mixture is between 0.03% and 0.2% by weight at a boron share of the master alloy powder of less than 10% by weight, that the weight ratio between the nickel and the boron share of the powder mixture exceeds 5 and that the master alloy powder has an average particle size of between 10 and 90 μm.  
   
   
       2 . A method according to  claim 1 , wherein the boron content of the powder mixture lies between 0.10% and 0.15% by weight.  
   
   
       3 . A method according to  claim 1 , wherein the powder mixture has a carbon content of between 0.15% and 0.8% by weight.