Mixed powder for powder metallurgy

Abstract

A mixed powder for powder metallurgy according to an embodiment of the present invention contains an iron-based powder as a main component and further contains a powder of at least one sulfide selected from CaS, MnS, and MoS2; and a powder wherein a percentage content of magnesium oxide is greater than or equal to 0.005% by mass and less than or equal to 0.025% by mass, wherein the magnesium oxide has an average particle size D50 of greater than or equal to 0.5 μm and less than or equal to 5.0 μm.

1 . A mixed powder suitable for powder metallurgy, the powder comprising:
 an iron-comprising powder as a main component;   a first powder comprising CaS, MnS, and/or MoS 2 , as a sulfide; and   a second powder having percentage content of magnesium oxide in a range of from 0.005 to 0.025 mass %, based on total mixed powder weight,   wherein the magnesium oxide has an average particle size D50 in a range of from 0.5 to 5.0 μm.   
     
     
         2 . The powder of  claim 1 , wherein the sulfide is present in a range of from 0.04 to 0.20 mass %. 
     
     
         3 . The powder of  claim 1 , wherein the first powder comprises CaS. 
     
     
         4 . The powder of  claim 1 , wherein the first powder comprises MnS. 
     
     
         5 . The powder of  claim 1 , wherein the first powder comprises CaS and MnS. 
     
     
         6 . The powder of  claim 1 , wherein the first powder comprises MoS 2 . 
     
     
         7 . The powder of  claim 1 , wherein the first powder comprises CaS and MOS 2 . 
     
     
         8 . The powder of  claim 1 , wherein the first powder comprises MnS and MoS7. 
     
     
         9 . The powder of  claim 1 , wherein the first powder comprises CaS, MnS, and MoS 2 . 
     
     
         10 . The powder of  claim 1 , wherein the magnesium oxide has an average particle size D50 in a range of from 0.7 to 3.0 μm. 
     
     
         11 . The powder of  claim 1 , further comprising:
 copper in an amount of from 0.8 to 3.0 mass %, based on the total mixed powder weight.   
     
     
         12 . The powder of  claim 1 , wherein the iron-comprising powder is present in an amount of at least 95.86 mass %, based on the total mixed powder weight. 
     
     
         13 . The powder of  claim 1 , comprising the iron in an amount of at least 95.86 mass %, based on the total mixed powder weight. 
     
     
         14 . The powder of  claim 1 , wherein the iron-comprising powder is non-alloyed steel. 
     
     
         15 . The powder of  claim 1 , wherein the iron-comprising powder is at least partially alloyed steel. 
     
     
         16 . The powder of  claim 1 , wherein the iron-comprising powder further comprises copper, nickel, chromium, and/or molybdenum. 
     
     
         17 . The powder of  claim 2 , wherein the sulfide is present in at least 0.06 mass %. 
     
     
         18 . The powder of  claim 2 , wherein the sulfide is present in at most 0.18 mass %. 
     
     
         19 . The powder of  claim 1 , wherein the sulfide has an average particle size D50 in a range of from 1.0 to 10 μm.