Precision forging of titanium

Claim 2

The titanium forging process that comprises: preparing a quantity of titanium or titanium alloy stock shaped to fit within a cavity in a segmented zero draft die and having a volume approximately equal to that of a forged part to be manufactured in the die; applying a protective coating to said stock; heating said coated stock and said segmented zero draft die while separted to approximately a predetermined optimum forging temperature for said stock at least as high as about 1200° F; coating all segments of said die with a lubricant before positioning the stock therein; positioning the heated stock in the heated die; heating the die and contained stock further after assembly together and as necessary to give the combination said forging temperature; applying forging force to said heated segmented die to deform the heated stock partially, but not completely, toward the shape of said cavity; separating the sections of said segmented die and removing the partially forged stock therefrom; applying a protective coating again to said partially forged stock; reheating said partially forged stock and said segmented die while separated to said forging temperature; coating said die segments again with a lubricant before placing the stock therein for a second time; repositioning said heated partially forged stock in the segmented die; reheating the die and stock together; applying forging force again to the heated die to further deform the heated partially forged stock toward the shape of said cavity; and separating the die sections and removing the forged stock therefrom.

Claim 3

The titanium forging process as recited in claim 1, including placing the heated die and contained stock within a holder prior to the initial application of forging force to the die, and prior to the second application of forging force to the die; and maintaining the sections of said segmented die in assembled condition by said holder during each of said applications of forging force to the die.

Claim 4

The titanium forging process as recited in claim 1, including placing the heated die and contained heated stock together in a holder before the initial application of forging force to the die, and before the second application of forging force to the die; and preheating said holder, before each placement of the die and stock therein, to a temperature far above ambient temperature but less than the temperature of the die and stock.

Claim 5

The titanium forging process as recited in claim 1, in which said second application of forging force to the heated die is continued until the heated previously partially forged stock is completely forged to the shape of the die cavity.

Claim 6

The titanium forging process as recited in claim 1, in which said second application of forging force to the die does not deform the stock completely to the shape of said cavity; said process including further deforming the partially forged stock, ultimately to a shape corresponding substantially exactly to that of the die cavity, by repeating at least one additional time, and more times if necessary, the steps of applying a protective coating to the partially forged stock, reheating the partially forged stock and segmented die separately to approximately forging temperature, repositioning the heated partially forged stock in the heated segmented die coated with a lubricant, reheating the die and stock together, applying forging force again to the heated die to further deform the heated partially forged stock toward the shape of the cavity, and separating the die sections and removing the forged stock therefrom.

Claim 7

The titanium forging process as recited in claim 1, in which said lubricant with which the die is coated before each placement of the stock therein is a graphite suspension.

Claim 8

The titanium forging process as recited in claim 1, in which said protective coating which is applied to the stock before each heating step is a liquid containing glass grit and adapted to protect the stock against oxidation when heated to said forging temperature.

Claim 9

The titanium forging process as recited in claim 1, in which said cavity in the segmented die has no-draft surfaces and forms corresponding no-draft surfaces on the forged stock from which the die is separable by virtue of its segmented construction.

Claim 10

The titanium forging process as recited in claim 1, in which said forging temperature to which the stock and die are heated is between about 1200° and 1950° F.

Claim 11

The titanium forging process as recited in claim 1, in which said forging temperature to which the stock and die are heated is between about 1700° and 1750° F.

Claim 12

The titanium forging process as recited in claim 1, including removing flashing from the partially forged stock after the first forging step and before said reheating of the stock and die.

Claim 13

The titanium forging process as recited in claim 1, including cleaning said lubricant from the sections of the segmented die after the first application of forging force thereto and after removal of the stock thereform, and recoating the die sections with lubricant before repositioning the stock and the die for the second application of forging force thereto.

Claim 14

A precision forged product of titanium or titanium alloy manufactured by the process recited in claim 1.

Claim 15

A precision forged product of titanium or titanium alloy manufactured by the process recited in claim 3.

Claim 16

A precision forged product of titanium or titanium alloy manufactured by the product recited in claim 5.

Claim 17

The titanium forging process that comprises: preparing a quantity of titanium or titanium alloy stock shaped to fit within a cavity in a segmented die and having a volume approximately equal to that of a forged part to be manufactured in the die; coating all of the surfaces of said stock with a layer of material including glass grit in a liquid carrier, which material is capable of protecting said surfaces of the stock against oxidation when heated to the forging temperature of the stock; heating said coated stock and said segmented die while separate to appoximately the forging temperature of the stock; coating the heated die with a graphite suspension lubricant; positioning the heated stock in the heated die; heating the die and contained stock together to said forging temperature; preheating a die holder to a temperature several hundred degrees above ambient temperature but much lower than the temperature of the stock and segmented die; then placing the heated die and the contained stock together in said holder; applying forging force to said heated segmented die in said holder to deform the stock partially, but not completely toward the shape of said cavity; removing the die and stock from the holder and separating the sections of the segmented die and removing the partially forged stock therefrom; allowing the stock to cool; removing flashing from the stock; applying a second coating of heat resistant glass grit in a liquid carrier to the srufaces of said partially forged stock; cleaning the surfaces of the sections of the segmented die; reheating the partially forged coated stock and the segmented die while separate to essentially said forging temperature; recoating the heated sections of the segmented die with graphite suspension lubricant; repositioning the partially forged stock in the segmented die; reheating the die and contained stock together; placing the die and stock together in said holder while the latter is at a temperature several hundred degrees above ambient but much lower than the temperature of the die and stock; applying forging force again to the die while in said holder to further deform the stock toward the shape of said cavity; and removing the die sections and forged stock from the holder and separating the die sections from the stock.

Claim 18

The titanium forging process that comprises: preparing a quantity of titanium or titanium alloy stock shaped to fit within a cavity in a segmented die and having a volume approximately equal to that of a forged part to be manufactured in the die; coating all of the surfaces of said stock with a layer of material including glass grit in a liquid carrier, which material is capable of protecting said surfaces of the stock against oxidation when heated to the forging temperature of the stock; heating said coated stock and said segmented die while separate to appoximately the forging temperature of the stock; coating the heated die with a graphite suspension lubricant; positioning the heated stock in the heated die; heating the die and contained stock together to said forging temperature; preheating a die holder to a temperature several hundred degrees above ambient temperature but much lower than the temperature of the stock and segmented die; then placing the heated die and the contained stock together in said holder; applying forging force to said heated segmented die in said holder to deform the stock partially, but not completely toward the shape of said cavity; removing the die and stock from the holder and separating the sections of the segmented die and removing the partially forged stock therefrom; allowing the stock to cool; removing flashing from the stock; applying a second coating of heat resistant glass grit in a liquid carrier to the srufaces of said partially forged stock; cleaning the surfaces of the sections of the segmented die; reheating the partially forged coated stock and the segmented die while separate to essentially said forging temperature; recoating the heated sections of the segmented die with graphite suspension lubricant; repositioning the partially forged stock in the segmented die; reheating the die and contained stock together; placing the die and stock together in said holder while the latter is at a temperature several hundred degrees above ambient but much lower than the temperature of the die and stock; applying forging force again to the die while in said holder to further deform the stock toward the shape of said cavity; and removing the die sections and forged stock from the holder and separating the die sections from the stock.

Claim 19

The titanium forging process as recited in claim 16, including further deforming said stock, ultimately to a shape corresponding closely to the shape of said die cavity, by repeating at least one additional time, and more times if necessary, the steps of cleaning the die sections, removing flashing from the partially forged stock, applying a protective coating to the stock, heating the stock and die sections while separate to forging temperatures, positioning the reheated stock in the die, heating the die and contained stock together, placing the die and stock in the holder with the latter at a temperature above ambient temperature but less than that of the die and stock, applying forging force to the die to deform the stock further toward the shape of said cavity, and removing the die and forged stock from the holder and separating the die sections from the stock.

Claim 20

A forged titanium or titanium alloy product manufactured by the process recited in claim 17.