Mixed powder for powder metallurgy and green compact using the same

Abstract

A mixed powder for powder metallurgy to be used as a feedstock of a green compact includes an iron powder and/or an iron alloy powder, a component for improving mechanical properties, and a thermosetting resin powder. In the mixed powder, the thermosetting resin powder is composed of at least one resin selected from the group consisting of an epoxy-polyester-based resin, an epoxy-based resin, and an acrylic-based resin. In addition, the average particle diameter of the thermosetting resin powder is 100 μm or less, and the content of the thermosetting resin powder relative to the total amount of the iron powder and/or the iron alloy powder is 0.05 to 1.0 mass percent.

1 - 5 . (canceled)  
   
   
       6 . A method for producing a sintered compact, the method comprising: 
 making a mixed powder by mixing 
 an iron powder and/or an iron alloy powder,  
 a component for improving mechanical properties, and  
 a thermosetting resin powder;  
   forming the mixed powder into a green compact;    performing a heat treatment and then a cutting operation on the green compact; and    sintering the green compact after the cutting operation, wherein    the component for improving mechanical properties is at least one selected from the group consisting of copper, nickel, chromium, molybdenum, graphite, and manganese sulfide;    the thermosetting resin powder comprises at least one resin selected from the group consisting of an epoxy-polyester-based resin, an epoxy-based resin, and an acrylic-based resin;    the average particle diameter of the thermosetting resin powder is 100 μm or less; and    the content of the thermosetting resin powder relative to the total amount of the iron powder and/or the iron alloy powder is 0.05 to 1.0 mass percent.    
   
   
       7 . The method according to  claim 6 , further comprising mixing a lubricant into the mixed powder.  
   
   
       8 . The method according to  claim 7 , wherein the lubricant is at least one compound selected from the group consisting of ethylenebisstearamide, stearamide, zinc stearate, and lithium stearate.  
   
   
       9 . The method according to  claim 6 , wherein the component for improving mechanical properties is at least one selected from the group consisting of copper, chromium, molybdenum and graphite.  
   
   
       10 . The method according to  claim 6 , wherein 
 the component for improving mechanical properties is at least one selected from the group consisting of copper, chromium and molybdenum; and    the content of the component for improving mechanical properties relative to the total amount of the iron powder and/or the iron alloy powder is 0.1 to 4 mass percent.    
   
   
       11 . The method for producing a sintered compact according to  claim 6 , wherein 
 the component for improving mechanical properties is graphite; and    the content of the component for improving mechanical properties relative to the total amount of the iron powder and/or the iron alloy powder is 0.1 to 1 mass percent.    
   
   
       12 . The method for producing a sintered compact according to  claim 7 , wherein the component of the lubricant relative to the total amount of the iron powder and/or the iron alloy powder is 0.05 to 1.0 mass percent.  
   
   
       13 . The method for producing a sintered compact according to  claim 6 , wherein the average particle diameter of the thermosetting resin powder is in a range of 30 to 60 μm.  
   
   
       14 . A sintered compact produced by the method of  claim 6.