Method of producing a high temperature metal powder component

Claim 1

A method of producing a fully dense high temperature metallic component from high temperature metal powder comprising: filling a centrally located mold cavity with a high temperature metal powder, said cavity having a shape substantially conforming to the dimensional configuration of the component to be formed as measured in the lateral direction, said cavity having a shape uniformly larger than the dimensional configuration of the component to be formed as measured in the vertical direction, said mold composed of a material having substantially the same flow stress throughout, said material able to maintain dimensional stability in a viscoelastic state at a temperature of from approximately 950° to 1300° C., said mold having at least one passageway therethrough leading to said cavity, heating the filled mold to a temperature greater than half the melting temperature of the powder in degrees centigrade and less than the melting temperature of the powder, while applying a vacuum to the cavity of at least twenty microns of mercury, closing the mold to provide a vacuum tight seal, axially compressing the sealed mold while maintaining the mold within the above heated temperature range, said axial compression being in the vertical direction with respect to the cavity dimensions at a pressure of at least 345 megapascals to effect plastic flow of the metal and mold, while restricting the mold about its lateral periphery with respect to the cavity dimensions, holding said mold in a compressed state for less than five minutes including at least 20 seconds after attaining maximum pressure, and separating the mold materials from the component.

Claim 2

A method of producing a fully dense high temperature metallic component from high temperature metal powder comprising: filling a centrally located mold cavity with a high temperature metal powder, said cavity having a shape substantially conforming to the dimensional configuration of the component to be formed as measured in the lateral direction, said cavity having a shape uniformly larger than the dimensional configuration of the component to be formed as measured in the vertical direction, said mold composed of a material having substantially the same flow stress throughout, said material able to maintain dimensional stability in a viscoelastic state at a temperature of from approximately 950° to 1300° C., said mold having at least one passageway therethrough leading to said cavity, heating the filled mold to a temperature greater than half the melting temperature of the powder in degrees centigrade and less than the melting temperature of the powder, while applying a vacuum to the cavity of at least twenty microns of mercury, closing the mold to provide a vacuum tight seal, axially compressing the sealed mold while maintaining the mold within the above heated temperature range, said axial compression being in the vertical direction with respect to the cavity dimensions at a pressure of at least 345 megapascals to effect plastic flow of the metal and mold, while restricting the mold about its lateral periphery with respect to the cavity dimensions, holding said mold in a compressed state for less than five minutes including at least 20 seconds after attaining maximum pressure, and separating the mold materials from the component.

Claim 10

A method of producing a fully dense titanium alloy component having a low thickness to diameter ratio comprising the steps of: filling a centrally located mold cavity with a titanium alloy powder having a flow stress greater than that of the mold material, said mold being ceramic with a steel shell therearound, said shell having a thickness of at least 0.20 centimeters, with a centrally located die cavity therein, said cavity having a shape substantially conforming to the dimensional configuration of the dimensional configuration of the titanium alloy component to be formed, as measured in the lateral direction, said cavity having a shape uniformly larger than the dimensional configuration of the titanium alloy component to be formed as measured in the vertical direction, said ceramic mold composed of 20-35 parts by weight calcium aluminate, 60-70 parts by weight fused silica, and 3-15 parts by weight zinc borosilicate frit having substantially the same flow stress throughout, said mold material able to maintain dimensional stability in a viscoelastic state at a temperature of approximately 950° to 1300° C., said mold having at least one passageway therethrough leading to said cavity, heating the filled mold to a temperature greater than half the melting temperature of the titanium alloy powder in degrees centigrade and less than the melting temperature of the titanium alloy powder, while applying a vacuum to the cavity of at least approximately 20 microns of mercury, closing the mold to provide a vacuum tight seal, axially compressing the sealed mold while maintaining the mold within the above heating range, said axial compression being in the vertical direction with respect to the cavity dimensions at a pressure of at least 345 megapascals to effect plastic flow of the metal and mold while restricting the mold about its lateral periphery with respect to cavity dimensions, holding the mold in a compressed state for less than five minutes including at least 20 seconds after attaining maximum pressure, and separating the mold material from the titanium component.

Claim 11

A method of producing a fully dense titanium alloy component having a low thickness to diameter ratio comprising the steps of: filling a centrally located mold cavity with a titanium alloy powder having a flow stress greater than that of the mold material, said mold being ceramic with a steel shell therearound, said shell having a thickness of at least 0.20 centimeters, with a centrally located die cavity therein, said cavity having a shape substantially conforming to the dimensional configuration of the dimensional configuration of the titanium alloy component to be formed, as measured in the lateral direction, said cavity having a shape uniformly larger than the dimensional configuration of the titanium alloy component to be formed as measured in the vertical direction, said ceramic mold composed of 20-35 parts by weight calcium aluminate, 60-70 parts by weight fused silica, and 3-15 parts by weight zinc borosilicate frit having substantially the same flow stress throughout, said mold material able to maintain dimensional stability in a viscoelastic state at a temperature of approximately 950° to 1300° C., said mold having at least one passageway therethrough leading to said cavity, heating the filled mold to a temperature greater than half the melting temperature of the titanium alloy powder in degrees centigrade and less than the melting temperature of the titanium alloy powder, while applying a vacuum to the cavity of at least approximately 20 microns of mercury, closing the mold to provide a vacuum tight seal, axially compressing the sealed mold while maintaining the mold within the above heating range, said axial compression being in the vertical direction with respect to the cavity dimensions at a pressure of at least 345 megapascals to effect plastic flow of the metal and mold while restricting the mold about its lateral periphery with respect to cavity dimensions, holding the mold in a compressed state for less than five minutes including at least 20 seconds after attaining maximum pressure, and separating the mold material from the titanium component.