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US4770673A Expired / Lapsed US ⏱️ 0.0 years remaining

Ceramic cutting tool inserts

Assignee: Corning Glass Works
•
Filing: 1987-10-09
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Granted: 1988-09-13
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Expires: 2007-10-09
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Abstract

Abstract This invention is concerned with the production of a hard, tough, thermally conductive ceramic cutting tool insert consisting essentially of a zirconia alloy in a hard refractory ceramic insert. The ceramic cutting tool insert exhibits performance conducive to use in turning operations and/or milling operations.

Inventors

  • 👤 Thomas D. Ketcham
  • 👤 David S. Weiss

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 19:53
CPC Classifications
B; B22; B22F; B22F7/00; B22F7/02; B22F7/04; B24; B24D; B24D3/00; B24D3/02; B24D3/04; B24D3/06; B24D3/34

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 183 words
A ceramic cutting tool insert exhibiting a hardness greater than 15 GPa, a toughness greater than 6 MPa√m, and a thermal conductivity greater than 14 Wm -1 °K. -1 consisting essentially, expressed in terms of percent by weight, of 20-45% zirconia alloy and 55-80% hard refractory ceramic matrix, said alloy consisting essentially, expressed in terms of mole percent on the oxide basis, of 1-4% of a toughening agent selected from the group consisting of YNbO 4 , YTaO 4 , MNbO 4 , MTaO 4 , and mixtures thereof, wherein M consists of a cation which replaces a Y cation on a mole basis selected from the group consisting of Mg +2 , Ca +2 , Sc +3 , and a rare earth metal ion selected from the group consisting of La +3 , Ce +4 , Ce +3 , Pr +3 , Nd +3 , Sm +3 , Eu +3 , Gd +3 , Tb +3 , Dy +3 , Ho +3 , Er +3 , Tm +3 , Yb +3 , Lu +3 , and mixtures thereof, and the remainder zirconia.
Claim 2
Dependent Claim 183 words
A ceramic cutting tool insert exhibiting a hardness greater than 15 GPa, a toughness greater than 6 MPa√m, and a thermal conductivity greater than 14 Wm -1 °K. -1 consisting essentially, expressed in terms of percent by weight, of 20-45% zirconia alloy and 55-80% hard refractory ceramic matrix, said alloy consisting essentially, expressed in terms of mole percent on the oxide basis, of 1-4% of a toughening agent selected from the group consisting of YNbO 4 , YTaO 4 , MNbO 4 , MTaO 4 , and mixtures thereof, wherein M consists of a cation which replaces a Y cation on a mole basis selected from the group consisting of Mg +2 , Ca +2 , Sc +3 , and a rare earth metal ion selected from the group consisting of La +3 , Ce +4 , Ce +3 , Pr +3 , Nd +3 , Sm +3 , Eu +3 , Gd +3 , Tb +3 , Dy +3 , Ho +3 , Er +3 , Tm +3 , Yb +3 , Lu +3 , and mixtures thereof, and the remainder zirconia.
Claim 3
Dependent Claim 47 words
A ceramic cutting tool insert according to claim 1 wherein said hard refractory ceramic matrix is selected from the group consisting of alumina, Al 2 O 3 -Cr 2 O 3 solid solution, sialon, silicon carbide, silicon nitride, titanium carbide, titanium diboride, zirconium carbide, and mixtures thereof.
Claim 4
Dependent Claim 25 words
A ceramic cutting tool insert according to claim 2 wherein Cr 2 O 3 is present in an amount up to about 5 mole %.
Claim 5
Dependent Claim 23 words
A ceramic cutting tool insert according to claim 1 also including up to 35% by volume total of refractory ceramic fibers and/or whiskers.
Claim 6
Dependent Claim 40 words
A ceramic cutting tool insert according to claim 4 wherein said refractory ceramic fibers and/or whiskers are selected from the group consisting of alumina, mullite, sialon, silicon carbide, silicon nitride, AlN, BN, B 4 C, zirconia, silicon oxycarbide, and spinel.
Claim 7
Independent Claim 232 words
A method for producing a conductive ceramic cutting tool insert exhibiting a hardness greater than 15 GPa, a toughness greater than 6 MPa√m, and a thermal conductivity greater than 14 Wm -1 °K. -1 , comprising the steps of: (a) forming a mixture of powders consisting essentially of, expressed in terms of percent by weight, 20-45% zirconia alloy and 55-80% hard refractory ceramic, said alloy consisting essentially, expressed in terms of mole percent on the oxide basis, of 1-4% of a toughening agent selected from the group consisting of YNbO 4 , YTaO 4 , MNbO 4 , MTaO 4 , and mixtures thereof, wherein M consists of a cation which replaces a Y cation on a mole basis selected from the group consisting of Mg +2 , Ca +2 , Sc +3 , and a rare earth metal ion selected from the group consisting of La +3 , Ce +4 , Ce +3 , Pr +3 , Nd +3 , Sm +3 , Eu +3 , Gd +3 , Tb +3 , Dy +3 , Ho +3 , Er +3 , Tm +3 , Yb +3 , Lu +3 , and mixtures thereof, and the remainder zirconia; (b) shaping said mixture into a desired configuration for a cutting tool insert; and (c) sintering said shaped mixture at temperatures between about 1100° C.-1700° C. to form a hard, tough, thermally conductive body.
Claim 8
Independent Claim 232 words
A method for producing a conductive ceramic cutting tool insert exhibiting a hardness greater than 15 GPa, a toughness greater than 6 MPa√m, and a thermal conductivity greater than 14 Wm -1 °K. -1 , comprising the steps of: (a) forming a mixture of powders consisting essentially of, expressed in terms of percent by weight, 20-45% zirconia alloy and 55-80% hard refractory ceramic, said alloy consisting essentially, expressed in terms of mole percent on the oxide basis, of 1-4% of a toughening agent selected from the group consisting of YNbO 4 , YTaO 4 , MNbO 4 , MTaO 4 , and mixtures thereof, wherein M consists of a cation which replaces a Y cation on a mole basis selected from the group consisting of Mg +2 , Ca +2 , Sc +3 , and a rare earth metal ion selected from the group consisting of La +3 , Ce +4 , Ce +3 , Pr +3 , Nd +3 , Sm +3 , Eu +3 , Gd +3 , Tb +3 , Dy +3 , Ho +3 , Er +3 , Tm +3 , Yb +3 , Lu +3 , and mixtures thereof, and the remainder zirconia; (b) shaping said mixture into a desired configuration for a cutting tool insert; and (c) sintering said shaped mixture at temperatures between about 1100° C.-1700° C. to form a hard, tough, thermally conductive body.
Claim 9
Dependent Claim 21 words
The method of claim 6 wherein said mixture contains no particles or agglomerates of particles greater than 50 microns in diameter.
Claim 10
Dependent Claim 43 words
The method of claim 6 wherein the hard refractory ceramic matrix is selected from the group consisting of alumina, Al 2 O 3 -Cr 2 O 3 solid solution, sialon, silicon carbide, silicon nitride, titanium carbide, titanium diboride, zirconium carbide, and mixtures thereof.
Claim 11
Dependent Claim 26 words
The method of claim 6 wherein Cr 2 O 3 is included in said mixture of powder in an amount up to about 5 mole %.
Claim 12
Dependent Claim 23 words
The method of claim 6 wherein up to 35% by volume refractory ceramic fibers and/or whiskers is included in said mixture of powders.
Claim 13
Dependent Claim 37 words
The method of claim 10 wherein said refractory ceramic fibers and/or whiskers are selected from the group consisting of alumina, sialon, mullite, silicon carbide, silicon nitride, AlN, BN, B 4 C, zirconia, zircon, spinel, and silicon oxycarbide.
Claim 14
Independent Claim 270 words
A method for producing a conductive ceramic cutting tool insert exhibiting a hardness greater than 15 GPa, a toughness greater than 6 MPa√m, and a thermal conductivity greater than 14 Wm -1 °K. -1 , comprising the steps of: (a) forming a mixture of powders consisting essentially of a hard refractory ceramic, zirconia, a toughening agent selected from the group consisting of YNbO 4 , YTaO 4 , MNbO 4 , MTaO 4 , and mixtures thereof, wherein M consists of a cation which replaces a Y cation on a mole basis selected from the group consisting of Mg +2 , Ca +2 , Sc +3 , and a rare earth metal ion selected from the group consisting of La +3 , Ce +4 , Ce +3 , Pr +3 , Nd +3 , Sm +3 , Eu +3 , Gd +3 , Tb +3 , Dy +3 , Ho +3 , Er +3 , Tm +3 , Yb +3 , Lu +3 , and mixtures thereof or components which, when reacted together, will form said toughening agent, said powders being present in sufficient amounts and in the proper proportions to produce, upon sintering, a body consisting essentially, expressed in terms of percent by weight, of 20-45% zirconia alloy and 55-80% hard refractory ceramic, said alloy consisting essentially, expressed in terms of mole percent on the oxide basis, of 1-4% toughening agent and the remainder zirconia; (b) shaping said mixture into a desired configuration for a cutting tool insert; and (c) sintering said shaped mixture at temperatures between about 1100° C.-1700° C. to form a hard, tough, thermally conductive body.
Claim 15
Independent Claim 270 words
A method for producing a conductive ceramic cutting tool insert exhibiting a hardness greater than 15 GPa, a toughness greater than 6 MPa√m, and a thermal conductivity greater than 14 Wm -1 °K. -1 , comprising the steps of: (a) forming a mixture of powders consisting essentially of a hard refractory ceramic, zirconia, a toughening agent selected from the group consisting of YNbO 4 , YTaO 4 , MNbO 4 , MTaO 4 , and mixtures thereof, wherein M consists of a cation which replaces a Y cation on a mole basis selected from the group consisting of Mg +2 , Ca +2 , Sc +3 , and a rare earth metal ion selected from the group consisting of La +3 , Ce +4 , Ce +3 , Pr +3 , Nd +3 , Sm +3 , Eu +3 , Gd +3 , Tb +3 , Dy +3 , Ho +3 , Er +3 , Tm +3 , Yb +3 , Lu +3 , and mixtures thereof or components which, when reacted together, will form said toughening agent, said powders being present in sufficient amounts and in the proper proportions to produce, upon sintering, a body consisting essentially, expressed in terms of percent by weight, of 20-45% zirconia alloy and 55-80% hard refractory ceramic, said alloy consisting essentially, expressed in terms of mole percent on the oxide basis, of 1-4% toughening agent and the remainder zirconia; (b) shaping said mixture into a desired configuration for a cutting tool insert; and (c) sintering said shaped mixture at temperatures between about 1100° C.-1700° C. to form a hard, tough, thermally conductive body.
Claim 16
Dependent Claim 21 words
The method of claim 12 wherein said mixture contains no particles or agglomerates of particles greater than 50 microns in diameter.
Claim 17
Dependent Claim 43 words
The method of claim 12 wherein the hard refractory ceramic matrix is selected from the group consisting of alumina, Al 2 O 3 -Cr 2 O 3 solid solution, sialon, silicon carbide, silicon nitride, titanium carbide, titanium diboride, zirconium carbide, and mixtures thereof.
Claim 18
Dependent Claim 26 words
The method of claim 12 wherein Cr 2 O 3 is included in said mixture of powder in an amount up to about 5 mole %.
Claim 19
Dependent Claim 22 words
The method of claim 12 wherein up to 35% by volume refractory ceramic fibers and/or whiskers are entrained in said shaped mixture.
Claim 20
Dependent Claim 37 words
The method of claim 16 wherein said refractory ceramic fibers and/or whiskers are selected from the group consisting of alumina, sialon, mullite, silicon carbide, silicon nitride, AlN, BN, B 4 C, zirconia, zircon, spinel, and silicon oxycarbide.

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-09-13 1992-03-14 1992-09-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-09-13 1996-03-14 1996-09-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-09-13 2000-03-14 2000-09-13 $7700.00 Window Closed / Lapsed

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