Sinter-hardening powder and their sintered compacts

Abstract

A sinter-hardening powder can yield a sintered compact with high strength, high hardness, and high density. A raw powder for sintering includes Fe as its primary component and also comprising 0.1-0.8 wt % C, 5.0-12.0 wt % Ni, 0.1-2.0 wt % Cr, and 0.1-2.0 wt % Mo, wherein the mean particle size of the raw powder for sintering is 20 μm or less. The sintered and tempered compact, without any quenching treatment, has high hardness, high strength, high density, and good ductility.

1 . A sinter-hardening raw powder comprising iron (Fe) as a primary composition and further comprising 0.1 to 0.8 wt % of Carbon (C), 5.0 to 12.0 wt % Nickel (Ni), 0.1 to 2.0 wt % chromium (Cr), and 0.1 to 2.0 wt % molybdenum (Mo), wherein a mean particle size of the raw powder for sintering is 20 μm or less. 
     
     
         2 . The sinter-hardening raw powder according to  claim 1 , further containing at least one element from among 2 wt % or less Cu, 1 wt % or less Ti, 1 wt % or less Al, 1 wt % or less Mn, 1 wt % or less Si, and 1 wt % or less of P. 
     
     
         3 . The sinter-hardening raw powder according to  claim 1 , containing 0.3-0.7 wt % of Carbon (C), 6.0-10.0 wt % Nickel (Ni), 0.3-1.5 wt % chromium (Cr), 0.2-1.0 wt % of molybdenum (Mo). 
     
     
         4 . The sinter-hardening raw powder according to  claim 2 , containing 0.1-1.0 wt % of Copper (Cu), 0.2-0.8 wt % of Manganese (Mn), and 0.1-0.5 wt % of Silicon (Si). 
     
     
         5 . The sinter-hardening raw powder according to  claim 1 , wherein a source of the carbon is from carbon-containing carbonyl iron powder. 
     
     
         6 . The sinter-hardening raw powder according to  claim 1 , wherein a source of the carbon is from carbon black powder. 
     
     
         7 . The sinter-hardening raw powder according to  claim 1 , wherein a source of the carbon is from graphite powder. 
     
     
         8 . The sinter-hardening raw powder according to  claim 1 , wherein the raw powder is elemental powder or ferroalloy powder or a mixture of the two. 
     
     
         9 . The sinter-hardening raw powder according to  claim 1 , wherein the iron is from carbonyl iron powder. 
     
     
         10 . The sinter-hardening raw powder according to  claim 1 , wherein the iron is from atomized iron powder. 
     
     
         11 . The sinter-hardening raw powder according to  claim 1 , wherein the iron is from reduced iron powder. 
     
     
         12 . A sintered compact, comprising compositions of the sinter-hardening raw powder according to  claim 1 .