Copper coated, iron-carbon eutectic alloy powders
First Claim
1. A method of preconditioning a master alloy intermediate powder useful in being blended with a base metal powder for making liquid-phase sintered shapes, comprising:
- (a) selecting an iron-carbon-prealloyed powder containing at least one alloying ingredient selected from the group consisting of manganese, chromium, molybdenum, nickel, copper, vanadium, said alloying ingredients each being present in an amount of about 2.5% by weight and the total of said alloying ingredients being in the range of 0.5-20% by weight,(b) sizing said iron-carbon-alloy powder to a mesh size of -100, and(c) substantially enveloping each particle of said iron-carbon-alloying powder with a metal which can be dissolved in said prealloyed powder and which is effective to act as a barrier to carbon diffusion in the solid state condition and which barrier metal remains substantially solid only up to the point of melting of said prealloyed powder, said envelope having a thickness of about 200 microns.
0 Assignments
0 Petitions
Accused Products
Abstract
A mechanical mixture of selected powders is subjected to compressive forces to define a pre-compact, the pre-compact then being subjected to liquid phase sintering for producing a raw alloy steel product which is more economical and has enhanced physical properties, particularly tensile strength as compared to sintered compacts produced by the prior art to date. The improvement in physical properties and processing technique results principally from the use of a mechanical mixture consisting of a base iron powder and a coated alloyed additive powder having selected alloying ingredients (such as manganese, nickel, molybdenum, in an iron-carbon system); the particles of the alloyed powder have a thin flash coating of a low melting metal, such as copper, to control carbon diffusion into the base iron powder during liquid phase sintering.
14 Citations
5 Claims
-
1. A method of preconditioning a master alloy intermediate powder useful in being blended with a base metal powder for making liquid-phase sintered shapes, comprising:
-
(a) selecting an iron-carbon-prealloyed powder containing at least one alloying ingredient selected from the group consisting of manganese, chromium, molybdenum, nickel, copper, vanadium, said alloying ingredients each being present in an amount of about 2.5% by weight and the total of said alloying ingredients being in the range of 0.5-20% by weight, (b) sizing said iron-carbon-alloy powder to a mesh size of -100, and (c) substantially enveloping each particle of said iron-carbon-alloying powder with a metal which can be dissolved in said prealloyed powder and which is effective to act as a barrier to carbon diffusion in the solid state condition and which barrier metal remains substantially solid only up to the point of melting of said prealloyed powder, said envelope having a thickness of about 200 microns. - View Dependent Claims (2, 3, 4, 5)
-
Specification