Steel powder composition and sintered body thereof

Abstract

A powder composition and a sintered body thereof are presented. The powder is a martensitic stainless steel powder for powder injection molding without deformation problems during sintering. The powder composition includes 0.80-1.40 weight percent (wt %) of carbon (C), less than 1.0 wt % of silicon (Si), less than 1.0 wt % of manganese (Mn), 15.0-18.0 wt % of chromium (Cr), 0.10-2.50 wt % of titanium (Ti), and the remainder iron (Fe). The powder can be sintered with a sintering temperature varying within 50° C. and can reach a high density without distortion, and thereby a good dimensional stability is obtained.

1 . A powder composition for martensitic stainless steels, comprising 0.80-1.40 weight percent (wt %) of carbon, greater than 0 wt % and less than 1.0 wt % of silicon, greater than 0 wt % and less than 1.0 wt % of manganese, 15.0-18.0 wt % of chromium, 0.7-2.50 wt % of titanium, and the rest of iron. 
     
     
         2 . The powder composition according to  claim 1 , further comprising 0.20-1.50 wt % of at least one of molybdenum, vanadium, and tungsten. 
     
     
         3 . The powder composition according to  claim 2 , wherein titanium in the steel powder composition is originated from a pre-alloyed powder. 
     
     
         4 . The powder composition according to  claim 2 , wherein titanium in the steel powder composition is originated from a titanium powder. 
     
     
         5 . The powder composition according to  claim 2 , wherein titanium in the steel powder composition is originated from a titanium-containing carbide powder. 
     
     
         6 . The powder composition according to  claim 5 , wherein the carbide powder has a mean particle size of less than 5 μm. 
     
     
         7 . The powder composition according to  claim 2 , wherein carbon in the steel powder composition is originated from graphite or carbon black powder. 
     
     
         8 . The powder composition according to  claim 1 , wherein titanium in the steel powder composition is originated from a pre-alloyed powder. 
     
     
         9 . The powder composition according to  claim 1 , wherein titanium in the steel powder composition is originated from a titanium powder. 
     
     
         10 . The powder composition according to  claim 1 , wherein titanium in the steel powder composition is originated from a titanium-containing carbide powder. 
     
     
         11 . The powder composition according to  claim 10 , wherein the carbide powder comprising titanium has an average particle size of less than 5 μm. 
     
     
         12 . The powder composition according to  claim 1 , wherein carbon in the steel powder composition is originated from graphite or carbon black powder. 
     
     
         13 . A sintered body, prepared from the powder composition according to  claim 1  through a sintering process. 
     
     
         14 . The sintered body according to  claim 13 , further comprising 0.20-1.50 wt % of at least one of molybdenum, vanadium, and tungsten.