Sinter-hardening powder and their sintered compacts

Abstract

The present invention relates to a sinter hardening powder that can yield a sintered compact with high strength. The present invention provides a raw powder for sintering, comprising Fe as its primary component and also comprising 0.1-0.8 wt % C, 3.5-12.0 wt % Ni, 0.1-7.0 wt % Cr, and 2.0 wt % or less of Mo, wherein the mean particle size of the raw powder for sintering is 150 μm or less. The sintered compact having high tensile strength, high hardness, and good ductility can be formed without performing the quenching process.

1 . A sinter hardening powder comprising iron (Fe) as its primary composition, 0.1 wt %-0.8 wt % of Carbon (C), 3.5 wt %-12.0 wt % Nickel (Ni), 0.1 wt %-7.0 wt % chromium (Cr), and 2.0 wt % or less of molybdenum (Mo), wherein a mean particle size of sinter hardening powders is 150 μm or less.  
     
     
         2 . The sinter hardening powder as recited in  claim 1 , further comprising at least one element selected from the group consisting of 2 wt % or less Copper (Cu), 1 wt % or less Titanium (Ti), 1 wt % or less Aluminum (Al), 1 wt % or less Manganese (Mn), 1 wt % or less Silicon (Si), 1 wt % or less Niobium (Nb), and 1 wt % or less of Phosphorous (P).  
     
     
         3 . The sinter hardening powder as recited in  claim 1 , wherein the content of Carbon (C) is between 0.3 wt %-0.7 wt %, the content of Nickel (Ni) is between 6.0 wt %-10.0 wt %, the content of chromium (Cr) is between 0.3 wt %-6.0 wt %, and the content of molybdenum (Mo) is between 0.1 wt %-1.0 wt %.  
     
     
         4 . The sinter hardening powder according to  claim 2 , wherein the content of Copper (Cu) is between 0.1 wt %-1.0 wt %, the content of Manganese (Mn) is between 0.1 wt %-0.8 wt %, and the content of Silicon (Si) is between 0.1 wt %-0.5 wt %.  
     
     
         5 . The sinter hardening powder as recited in  claim 1 , wherein a source of carbon is from graphite.  
     
     
         6 . The sinter hardening powder as recited in  claim 1 , wherein a source of carbon is from carbonyl iron powder.  
     
     
         7 . The sinter hardening powder as recited in  claim 1 , wherein the mean particle size of the sinter hardening powders is between 0.1 μm and 30 μm, and the content of chromium (Cr) is between 0.1 wt % and 2 wt %.  
     
     
         8 . The sinter hardening powder as recited in  claim 1 , wherein the mean particle size of the sinter hardening powders is between 30 μm and 150 μm, the content of chromium (Cr) is between 1 wt % and 6 wt %.  
     
     
         9 . The sinter hardening powder as recited in  claim 1 , wherein the sinter hardening powders are elemental powders, ferroalloy powders, or a mixture thereof.  
     
     
         10 . The sinter hardening powder as recited in  claim 9 , wherein the ferroalloy powders and the elemental powders are diffusion alloyed or chemically bonded together.  
     
     
         11 . A granulated powder for sintering manufactured using the sinter hardening powder as recited in  claim 1 , wherein a mean particle size of the granulated powder is between 20 μm-150 μm.  
     
     
         12 . The granulated powder for sintering as recited in  claim 11 , wherein the mean particle size of the granulated powder is between 40 μm-80 μm.  
     
     
         13 . A sintered compact manufactured using the sinter hardening powder as recited in  claim 1 .  
     
     
         14 . A sintered compact manufactured using the granulated powder as recited in  claim 11.