Powdered metal alloy composition for wear and temperature resistance applications and method of producing same

Patent metadata

Field	Value
Publication number	US-9546412-B2
Application number	US-41968309-A
Country	US
Kind code	B2
Filing date	Apr 7, 2009
Priority date	Apr 8, 2008
Publication date	Jan 17, 2017
Grant date	Jan 17, 2017

Abstract

A powder metal steel alloy composition for high wear and temperature applications is made by water atomizing a molten steel alloy composition containing C in an amount of at least 3.0 wt %; at least one carbide-forming alloy element selected from the group consisting of: Cr, V, Mo or W; an O content less than about 0.5 wt %, and the balance comprising essentially Fe apart from incidental impurities. The high carbon content reduces the solubility of oxygen in the melt and thus lowers the oxygen content to a level below which would cause the carbide-forming element(s) to oxidixe during water atomization. The alloy elements are thus not tied up as oxides and are available to rapidly and readily form carbides in a subsequent sintering stage. The carbon, present in excess, is also available for diffusing into one or more other admixed powders that may be added to the prealloyed powder during sintering to control microstructure and properties of the final part.

First claim

What is claimed is:

1. A pre-sintered powder metal composition, consisting essentially of:
C in an amount of about 3.8 wt %; Cr in an amount of about 13 wt %; V in an amount of about 4 wt %; Mo in an amount of about 1.5 wt %; Win an amount of about 2.5 wt %; an O content about 0.2 wt %, and the balance Fe and incidental impurities.

2. The composition of claim 1 , wherein said powder is either annealed or unannealed.

3. The composition of claim 1 , wherein the powder is mechanically ground.

4. The composition of claim 1 , wherein the powder is unground.

Assignees

• Christopherson Jr Denis B
• Farthing Leslie John
• Schoenwetter Todd
• L'Esperance Gilles
• Beaulieu Philippe
• Federal Mogul Corp

Inventors

• Christopherson Jr Denis B
• Farthing Leslie John
• Schoenwetter Todd
• L'Esperance Gilles
• Beaulieu Philippe

Classifications

• C22C38/36 Primary

  with more than 1.7% by weight of carbon · CPC title

• C22C33/0285

  with Cr, Co, or Ni having a minimum content higher than 5% · CPC title

• B22F9/082 Primary

  atomising using a fluid (using centrifugal force B22F9/10) · CPC title

• C22C33/0292

  with more than 5% preformed carbides, nitrides or borides · CPC title

• B22F1/00

  Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties · CPC title