Elevated temperature metal forming lubrication
AssigneeCleveland State University
InventorEdgar E. Graham
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Abstract
An improved method to lubricate a metal workpiece at elevated temperatures is described employing a novel polymer lubricant formed in situ. The novel lubricant is provided with a liquid mist of a lubricant preparation containing a vaporizable and polymerizable organic reactant in combination with graphite particulates being supplied to both workpiece and forming die at the elevated working temperatures.
Claims15
A method of forging a metal workpiece preheated to at least 800.degree. C. with a metal forging die at forming temperatures of at least 250.degree. C. which comprises the steps of:
- (a) contacting the shaping region of the forging die with an aqueous mist of a lubricant preparation containing at least 0.5 percent by volume of a vaporizable and polymerizable organic reactant selected from the group consisting of phosphate esters and phosphazene compounds in combination with graphite particulates,
- (b) vaporizing the applied organic reactant at the elevated forming temperatures,
- (c) polymerizing the vaporized organic reactant in the vapor phase upon further contacting the shaping region of the forging die with the preheated workpiece to form a solid polymer lubricant in the shaping region of the forging die,
- (d) forming the preheated metal workpiece in the lubricated forging die, and
- (e) removing the formed workpiece from the forging die.
A method of hot forging a ferrous alloy workpiece preheated to at least 800.degree. C. in a ferrous alloy forging die heated to about 150.degree. C. which comprises the steps of:
- (a) contacting the shaping region of the forging die under atmospheric conditions and while heated at the specified elevated temperature to an aqueous mist formed with a water-based emulsion containing at least 0.5 percent by volume of a vaporizable and polymerizable aromatic phosphate compound and graphite particulates,
- (b) vaporizing the applied aromatic phosphate compound at the elevated forging die temperature,
- (c) polymerizing the applied aromatic phosphate compound in the vapor-phase upon further contacting the shaping region of the forging die with the preheated workpiece to form a solid polymer lubricant in the shaping region of the forging die,
- (d) forging the preheated workpiece in the lubricated forging die, and
- (e) removing the forged workpiece from the forging die.
A lubricated metal forging die made by:
- (a) preheating a metal workpiece to an elevated temperature of at least 800.degree. C.,
- (b) transferring the preheated workpiece to the shaping region of a metal forging die,
- (c) concurrently contacting the shaping region of the metal forging die with an aqueous mist containing at least 0.5 percent by volume of a voporizable and polymerizable organic reactant selected from the group consisting of phosphate esters and phosphazene compounds in combination with graphite particulates,
- (d) vaporizing the organic reactant while in contact with the preheated workpiece and metal forging die,
- (e) polymerizing the vaporized organic reactant in the vapor-phase while in contact with the preheated workpiece and metal forging die to form a solid polymer lubricant in situ, and
- (f) depositing the solid polymer lubricant as a film on the contacted shaping region of the metal forging die.
Dependencies are inferred from the claim text.