Method of and apparatus for machining ceramic materials

Claim 1

A method of machining a workpiece of a ceramic material, comprising the steps of: bringing into contact with the workpiece a liquid electrolyte having at least one component which is chemically reactive with the ceramic material at an elevated temperature; applying to a limited zone of interface between said liquid electrolyte and said workpiece, localized energy of a magnitude sufficient to heat said liquid electrolyte and said material at said limited zone to said elevated temperature and to remove from the workpiece the locally heated material at said limited zone in a form at least partially chemically degenerated with said at least one component; and displacing, in a scanning manner, said limited zone acquiring said localized energy from one region to another on said workpiece along a programmed continuous path to continuously remove said material along said path from the workpiece, said localized energy being applied by irradiating said limited zone with an energy beam, said zone being displaced along said path by relatively displacing said energy beam and said workpiece along said programmed path, a portion of said localized energy being applied to said limited zone by disposing a pair of electrodes closely spaced apart from each other adjacent to said limited zone and effecting a succession of electrical discharges through said liquid electrolyte across said electrodes, said electrodes and said workpiece being also relatively displaced in a said scanning manner to displace said limited zone from one region to another on the workpiece along said programmed path.

Claim 2

A method of machining a workpiece of a ceramic material, comprising the steps of: bringing into contact with the workpiece a liquid electrolyte having at least one component which is chemically reactive with the ceramic material at an elevated temperature; applying to a limited zone of interface between said liquid electrolyte and said workpiece, localized energy of a magnitude sufficient to heat said liquid electrolyte and said material at said limited zone to said elevated temperature and to remove from the workpiece the locally heated material at said limited zone in a form at least partially chemically degenerated with said at least one component; and displacing, in a scanning manner, said limited zone acquiring said localized energy from one region to another on said workpiece along a programmed continuous path to continuously remove said material along said path from the workpiece, said localized energy being applied by irradiating said limited zone with an energy beam, said zone being displaced along said path by relatively displacing said energy beam and said workpiece along said programmed path, a portion of said localized energy being applied to said limited zone by disposing a pair of electrodes closely spaced apart from each other adjacent to said limited zone and effecting a succession of electrical discharges through said liquid electrolyte across said electrodes, said electrodes and said workpiece being also relatively displaced in a said scanning manner to displace said limited zone from one region to another on the workpiece along said programmed path.

Claim 5

A method of machining of a ceramic material, comprising the steps of: bringing into contact with the workpiece a liquid electrolyte having at least one component which is chemically reactive with the ceramic material at an elevated temperature; applying to a limited zone of interface between said liquid electrolyte and said workpiece, localized energy of a magnitude sufficient to heat said liquid electrolyte and said material at said limited zone to said elevated temperature and to remove from the workpiece the locally heated material at said limited zone in a form at least partially chemically degenerated with said at least one component; and displacing, in a scanning manner, said limited zone acquiring said localized energy from one region to another on said workpiece along a programmed continuous path to continuously remove said material along said path from the workpiece, said localized energy comprising at least two different forms of energy, a first of which is applied to said limited zone to heat it to said elevated temperature and a second of which is applied to said zone so heated by said first form of energy to mechanically facilitate removal of said locally degenerated ceramic material from the workpiece.

Claim 6

A method of machining of a ceramic material, comprising the steps of: bringing into contact with the workpiece a liquid electrolyte having at least one component which is chemically reactive with the ceramic material at an elevated temperature; applying to a limited zone of interface between said liquid electrolyte and said workpiece, localized energy of a magnitude sufficient to heat said liquid electrolyte and said material at said limited zone to said elevated temperature and to remove from the workpiece the locally heated material at said limited zone in a form at least partially chemically degenerated with said at least one component; and displacing, in a scanning manner, said limited zone acquiring said localized energy from one region to another on said workpiece along a programmed continuous path to continuously remove said material along said path from the workpiece, said localized energy comprising at least two different forms of energy, a first of which is applied to said limited zone to heat it to said elevated temperature and a second of which is applied to said zone so heated by said first form of energy to mechanically facilitate removal of said locally degenerated ceramic material from the workpiece.

Claim 7

A method of machining a workpiece of a ceramic material, comprising the steps of: bringing into contact with the workpiece a liquid electrolyte having at least one component which is chemically reactive with the ceramic material at an elevated temperature; applying to a limited zone of interface between said liquid electrolyte and workpiece, localized energy of a magnitude sufficient to heat said liquid electrolyte and said material at said limited zone to said elevated temperature and to remove from the workpiece the locally heated material at said limited zone in a form at least partially chemically degenerated with said at least one component; and displacing, in a scanning manner, said limited zone acquiring said localized energy from one region to another on said workpiece along a programmed continuous path to continuously remove said ceramic material along said path from the workpiece, said localized energy being applied to said limited zone by disposing a pair of electrodes so that they are spaced apart across a small gap adjacent to said zone and effecting a succession of electrical discharges through said liquid electrolyte across said electrodes, said electrodes and said workpiece being relatively displaced along said programmed path to displace said limited zone from one region to another on the workpiece.

Claim 8

A method of machining a workpiece of a ceramic material, comprising the steps of: bringing into contact with the workpiece a liquid electrolyte having at least one component which is chemically reactive with the ceramic material at an elevated temperature; applying to a limited zone of interface between said liquid electrolyte and workpiece, localized energy of a magnitude sufficient to heat said liquid electrolyte and said material at said limited zone to said elevated temperature and to remove from the workpiece the locally heated material at said limited zone in a form at least partially chemically degenerated with said at least one component; and displacing, in a scanning manner, said limited zone acquiring said localized energy from one region to another on said workpiece along a programmed continuous path to continuously remove said ceramic material along said path from the workpiece, said localized energy being applied to said limited zone by disposing a pair of electrodes so that they are spaced apart across a small gap adjacent to said zone and effecting a succession of electrical discharges through said liquid electrolyte across said electrodes, said electrodes and said workpiece being relatively displaced along said programmed path to displace said limited zone from one region to another on the workpiece.

Claim 12

An apparatus for machining a workpiece of a ceramic material, comprising: means for supplying onto the workpiece a liquid electrolyte having at least one component which is chemically reactive with the ceramic material at an elevated temperature; means for applying to a limited zone of interface between said liquid electrolyte and said workpiece, localized energy of a magnitude sufficient to heat said liquid electrolyte and said material at said limited zone to said elevated temperature and to remove from the workpiece the locally heated material at said limited zone in a form at least partially chemically degenerated with said at least one component; and means for displacing, in a scanning manner, said limited zone acquiring said localized energy from one region to another on said workpiece along a programmed continuous path to continuously remove said material along said path from the workpiece, said means for applying comprising a pair of electrodes juxtaposed with each other across a small gap spacing adjacent to said zone, and a power supply for energizing said electrodes to produce thereacross a succession of electrical discharges through said liquid electrolyte.

Claim 13

An apparatus for machining a workpiece of a ceramic material, comprising: means for supplying onto the workpiece a liquid electrolyte having at least one component which is chemically reactive with the ceramic material at an elevated temperature; means for applying to a limited zone of interface between said liquid electrolyte and said workpiece, localized energy of a magnitude sufficient to heat said liquid electrolyte and said material at said limited zone to said elevated temperature and to remove from the workpiece the locally heated material at said limited zone in a form at least partially chemically degenerated with said at least one component; and means for displacing, in a scanning manner, said limited zone acquiring said localized energy from one region to another on said workpiece along a programmed continuous path to continuously remove said material along said path from the workpiece, said means for applying comprising a pair of electrodes juxtaposed with each other across a small gap spacing adjacent to said zone, and a power supply for energizing said electrodes to produce thereacross a succession of electrical discharges through said liquid electrolyte.

Claim 19

A method of machining a workpiece of a dielectric material, comprising the steps of: flushing onto the workpiece a fluid having at least one component to which said dielectric material is normally inert but with which it becomes chemically reactive at an elevated temperature; irradiating a limited zone on said workpiece traversed by said flushing fluid, with an energy beam with localized energy of a magnitude sufficient to locally heat said dielectric material at said limited zone to said elevated temperature; applying to said limited zone further localized energy of a magnitude sufficient to mechanically dislodge from the workpiece the locally heated dielectric material at said zone in a form at least partially chemically degenerated with said at least one component and to permit the dislodged material to be carried away with said flushing fluid; and relatively displacing said energy beam and said workpiece automatically in a predetermined scanning manner to shift said limited zone of irradiation of said energy beam progressively over a programmed region of the workpiece so that the workpiece is selectively machined in said region.

Claim 20

A method of machining a workpiece of a dielectric material, comprising the steps of: flushing onto the workpiece a fluid having at least one component to which said dielectric material is normally inert but with which it becomes chemically reactive at an elevated temperature; irradiating a limited zone on said workpiece traversed by said flushing fluid, with an energy beam with localized energy of a magnitude sufficient to locally heat said dielectric material at said limited zone to said elevated temperature; applying to said limited zone further localized energy of a magnitude sufficient to mechanically dislodge from the workpiece the locally heated dielectric material at said zone in a form at least partially chemically degenerated with said at least one component and to permit the dislodged material to be carried away with said flushing fluid; and relatively displacing said energy beam and said workpiece automatically in a predetermined scanning manner to shift said limited zone of irradiation of said energy beam progressively over a programmed region of the workpiece so that the workpiece is selectively machined in said region.

Claim 24

A method of machining a workpiece of a dielectric material which becomes electrically conductive at an elevated temperature, comprising the steps of: flushing a conductive fluid in contact with the workpiece; irradiating a limited zone on said workpiece traversed by said flushing fluid, with an energy beam with localized energy of a magnitude sufficient to locally heat said dielectric material at said zone to said elevated temperature, thereby rendering said material at said limited zone selectively electrically conductive; disposing a pair of electrodes so that they are spaced apart from each other across a small gap adjacent said zone and effecting a succession of electrical discharges through said conductive fluid and said dielectric material rendered conductive at said zone adjacent said gap to erosively dislodge said material at said zone from the workpiece; and relatively displacing said energy beam and said electrodes on the one hand and said workpiece on the other hand in a predetermined scanning manner to shift said zone of localized heating and material dislodgment progressively over a programmed region of the workpiece so that the workpiece is selectively machined in said region.

Claim 25

A method of machining a workpiece of a dielectric material which becomes electrically conductive at an elevated temperature, comprising the steps of: flushing a conductive fluid in contact with the workpiece; irradiating a limited zone on said workpiece traversed by said flushing fluid, with an energy beam with localized energy of a magnitude sufficient to locally heat said dielectric material at said zone to said elevated temperature, thereby rendering said material at said limited zone selectively electrically conductive; disposing a pair of electrodes so that they are spaced apart from each other across a small gap adjacent said zone and effecting a succession of electrical discharges through said conductive fluid and said dielectric material rendered conductive at said zone adjacent said gap to erosively dislodge said material at said zone from the workpiece; and relatively displacing said energy beam and said electrodes on the one hand and said workpiece on the other hand in a predetermined scanning manner to shift said zone of localized heating and material dislodgment progressively over a programmed region of the workpiece so that the workpiece is selectively machined in said region.

Claim 26

An apparatus for machining a workpiece of a dielectric material, comprising: means for flushing onto the workpiece a solution having at least one component to which said dielectric material is normally inert but with which it at an elevated temperature becomes chemically reactive; means for irradiating a limited zone on said workpiece through said flushing solution with an energy beam with localized energy of a magnitude sufficient to locally heat said dielectric material flushed with said solution at said limited zone to said elevated temperature; means for applying to said limited zone further localized energy of a magnitude sufficient to mechanically dislodge from the workpiece the locally heated dielectric material at said zone in a form at least partly chemically degenerated with said at least one component and to permit the dislodged material to be carried away with said flushing solution; and numerically controlled drive means for relatively displacing said energy beam and said workpiece automatically in a predetermined scanning manner to shift said limited zone of irradiation of said energy beam progressively over a programmed region of the workpiece so that the workpiece is selectively machined in said region.

Claim 27

An apparatus for machining a workpiece of a dielectric material, comprising: means for flushing onto the workpiece a solution having at least one component to which said dielectric material is normally inert but with which it at an elevated temperature becomes chemically reactive; means for irradiating a limited zone on said workpiece through said flushing solution with an energy beam with localized energy of a magnitude sufficient to locally heat said dielectric material flushed with said solution at said limited zone to said elevated temperature; means for applying to said limited zone further localized energy of a magnitude sufficient to mechanically dislodge from the workpiece the locally heated dielectric material at said zone in a form at least partly chemically degenerated with said at least one component and to permit the dislodged material to be carried away with said flushing solution; and numerically controlled drive means for relatively displacing said energy beam and said workpiece automatically in a predetermined scanning manner to shift said limited zone of irradiation of said energy beam progressively over a programmed region of the workpiece so that the workpiece is selectively machined in said region.

Claim 28

An apparatus for machining a workpiece of dielectric material which becomes electrically conductive at an elevated temperature, comprising: means for flushing a liquid electrolyte in contact with the workpiece; means for irradiating a limited zone on said workpiece through said flushing liquid electrolyte and said workpiece with an energy beam with localized energy of a magnitude sufficient to locally heat said dielectric material at said limited zone to said elevated temperature, thereby rendering said material at said zone selectively electrically conductive; means including a pair of electrodes disposed spaced apart across a small gap adjacent said zone and a power supply for effecting a succession of electrical discharges through said liquid electrolyte and said material rendered conductive at said limited zone to remove said material at said zone from the workpiece; and numerically controlled drive means for relatively displacing said beam and said electrode on one part and said workpiece on the other part in a predetermined scanning manner to shift said zone of localized heating and material removal progressively over a programmed region of the workpiece so that the workpiece is selectively machined in said region.

Claim 29

An apparatus for machining a workpiece of dielectric material which becomes electrically conductive at an elevated temperature, comprising: means for flushing a liquid electrolyte in contact with the workpiece; means for irradiating a limited zone on said workpiece through said flushing liquid electrolyte and said workpiece with an energy beam with localized energy of a magnitude sufficient to locally heat said dielectric material at said limited zone to said elevated temperature, thereby rendering said material at said zone selectively electrically conductive; means including a pair of electrodes disposed spaced apart across a small gap adjacent said zone and a power supply for effecting a succession of electrical discharges through said liquid electrolyte and said material rendered conductive at said limited zone to remove said material at said zone from the workpiece; and numerically controlled drive means for relatively displacing said beam and said electrode on one part and said workpiece on the other part in a predetermined scanning manner to shift said zone of localized heating and material removal progressively over a programmed region of the workpiece so that the workpiece is selectively machined in said region.