Patents by Inventor Prem C. Jindal

Prem C. Jindal has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6612787
    Abstract: A chromium-containing coated cemented tungsten carbide cutting insert that has a substrate and a coating. The substrate comprises between about 5.7 and about 6.4 weight percent cobalt, between about 0.2 and about 0.8 weight percent chromium and the balance tungsten and carbon, and a coercive force of about 195 to 245 oersteds.
    Type: Grant
    Filed: August 11, 2000
    Date of Patent: September 2, 2003
    Assignee: Kennametal Inc.
    Inventors: Bernard North, Prem C. Jindal
  • Patent number: 6575671
    Abstract: A chromium-containing coated cemented tungsten carbide cutting insert that has a substrate and a coating. The substrate comprises between about 10.4 and about 12.7 weight percent cobalt, between about 0.2 and about 1.2 weight percent chromium.
    Type: Grant
    Filed: August 11, 2000
    Date of Patent: June 10, 2003
    Assignee: Kennametal Inc.
    Inventors: Bernard North, Prem C. Jindal
  • Patent number: 5879823
    Abstract: A coated cutting tool that has a rake face and a flank face with a cutting edge at the juncture of the rake and flanks faces, a substrate, and a coating bonded to the substrate. The coating has a coating scheme that includes a layer of a Group IVB metal-aluminum alloy applied by physical vapor deposition, and a layer of alumina applied by physical vapor deposition to the layer of the Group IVB metal-aluminum alloy.
    Type: Grant
    Filed: December 12, 1995
    Date of Patent: March 9, 1999
    Assignee: Kennametal Inc.
    Inventors: John J. Prizzi, Prem C. Jindal, William A. Bryant, Bernard North
  • Patent number: 5858181
    Abstract: A process for physical vapor deposition of a refractory coating such as titanium nitride on a nonconductive substrate such as a ceramic substrate and the coated substrate produced thereby. The nonconductive substrate is coated by cleaning the nonconductive substrate surfaces and then depositing a first layer of a refractory metal such as titanium metal on the nonconductive substrate by physical vapor deposition. A second layer of a refractory compound such as titanium nitride is then deposited on the first layer by physical vapor deposition to produce a coated nonconductive substrate having enhanced coating adhesion.
    Type: Grant
    Filed: August 25, 1993
    Date of Patent: January 12, 1999
    Assignee: Kennametal Inc.
    Inventors: Prem C. Jindal, Dennis T. Quinto
  • Patent number: 5395680
    Abstract: Provided is a coated cutting tool having a coating and a substrate. The coating includes at least one CVD layer which may have a residual tensile stress and at least one layer having a high residual compressive stress. The outermost layer of the coating is preferably the one containing residual compressive stresses. The substrate is a composite having hard refractory grains.
    Type: Grant
    Filed: July 2, 1993
    Date of Patent: March 7, 1995
    Assignee: Kennametal Inc.
    Inventors: Anakkavur T. Santhanam, Rajendra V. Godse, Dennis T. Quinto, Kenneth E. Undercoffer, Prem C. Jindal
  • Patent number: 5364209
    Abstract: Provided is a coated cutting tool having a coating and a substrate. The coating includes at least one chemical vapor deposited (CVD) layer and at least one physical vapor deposited (PVD) layer. The outermost layer of the coating is a PVD layer, containing residual compressive stresses. The substrate is a composite having hard refractory grains bonded together by a binder material.
    Type: Grant
    Filed: January 14, 1994
    Date of Patent: November 15, 1994
    Assignee: Kennametal Inc.
    Inventors: Anakkavur T. Santhanam, Rajendra V. Godse, Dennis T. Quinto, Kenneth E. Undercoffer, Prem C. Jindal
  • Patent number: 5325747
    Abstract: Provided is a coated cutting tool having a coating and a substrate. The coating includes at least one CVD layer which may have a residual tensile stress and at least one layer having a high residual compressive stress. The outermost layer of the coating is preferably the one containing residual compressive stresses. The substrate is a composite having hard refractory grains. The cutting tool has been found to be particularly useful in the machining of titanium alloys and superalloys.
    Type: Grant
    Filed: August 13, 1992
    Date of Patent: July 5, 1994
    Assignee: Kennametal Inc.
    Inventors: Anakkavur T. Santhanam, Rajendra V. Godse, Dennis T. Quinto, Kenneth E. Undercoffer, Prem C. Jindal, Roger A. Baillargeon, William D. Ewald
  • Patent number: 5266388
    Abstract: Provided is a coated cutting tool having a binder enriched substrate. The coating includes at least one CVD layer which may be in a state of residual tensile stress and at least one layer in a state of residual compressive stress.
    Type: Grant
    Filed: August 29, 1991
    Date of Patent: November 30, 1993
    Assignee: Kennametal Inc.
    Inventors: Anakkavur T. Santhanam, Rajendra V. Godse, George P. Grab, Dennis T. Quinto, Kenneth E. Undercoffer, Prem C. Jindal
  • Patent number: 5264297
    Abstract: A process for physical vapor deposition of a refractory coating such as titanium nitride on a nonconductive substrate such as a ceramic substrate and the coated substrate produced thereby. The nonconductive substrate is coated by cleaning the nonconductive substrate surfaces and then depositing a first layer of a refractory metal such as titanium metal on the nonconductive substrate by physical vapor deposition. A second layer of a refractory compound such as titanium nitride is then deposited on the first layer by physical vapor deposition to produce a coated nonconductive substrate having enhanced coating adhesion.
    Type: Grant
    Filed: April 1, 1992
    Date of Patent: November 23, 1993
    Assignee: Kennametal Inc.
    Inventors: Prem C. Jindal, Dennis T. Quinto
  • Patent number: 5250367
    Abstract: Provided is a coated cutting tool having a binder enriched substrate. The coating includes at least one chemical vapor deposited (CVD) layer and at least one physical vapor deposited (PVD) layer. The PVD layer contains residual compressive stresses.
    Type: Grant
    Filed: September 17, 1990
    Date of Patent: October 5, 1993
    Assignee: Kennametal Inc.
    Inventors: Anakkavur T. Santhanam, Rajendra V. Godse, George P. Grab, Dennis T. Quinto, Kenneth E. Undercoffer, Prem C. Jindal
  • Patent number: 5232318
    Abstract: Provided is a coated cutting tool having a coating and a substrate. The coating includes at least one CVD layer which may have a residual tensile stress and at least one layer having a high residual compressive stress. The outermost layer of the coating is preferably the one containing residual compressive stresses. The substrate is a composite having hard refractory grains.
    Type: Grant
    Filed: August 29, 1991
    Date of Patent: August 3, 1993
    Assignee: Kennametal Inc.
    Inventors: Anakkavur T. Santhanam, Rajendra V. Godse, Dennis T. Quinto, Kenneth E. Undercoffer, Prem C. Jindal
  • Patent number: 5143488
    Abstract: Provided is a coated cutting tool having a coating and a substrate. The coating includes at least one chemical vapor deposited (CVD) layer and at least one physical vapor deposited (PVD) layer. The outermost layer of the coating is a PVD layer, containing residual compressive stresses. The substrate is a composite having hard refractory grains bonded together by a binder material.
    Type: Grant
    Filed: September 17, 1990
    Date of Patent: September 1, 1992
    Assignee: Kennametal Inc.
    Inventors: Anakkavur T. Santhanam, Rajendra V. Godse, Dennis T. Quinto, Kenneth E. Undercoffer, Prem C. Jindal
  • Patent number: 4247734
    Abstract: A flexible mounting for thermocouples for vacuum electric furnaces is described, which is particularly suitable for furnaces for nitrided or carburized case formation to avoid line of sight metallic deposition on the mounting from sputtering in the furnace and which could result in shorting, spaced shields being provided on the thermocouple mounting for this purpose.
    Type: Grant
    Filed: March 5, 1979
    Date of Patent: January 27, 1981
    Assignee: Abar Corporation
    Inventors: Rush B. Gunther, Prem C. Jindal
  • Patent number: 4246434
    Abstract: A work support for vacuum electric furnaces is provided for furnaces in which work pieces to be processed are placed inside a vacuum electric furnace chamber which is evacuated with a mechanical pump and then backfilled with a partial pressure of gas containing nitrogen, such as nitrogen or ammonia, or a hydrocarbon such as methane, or mixtures thereof. The work pieces to be processed are electrically connected to the negative (cathode) terminal of a D.C. power supply, and insulated from the chamber wall which is connected to positive terminal of the D.C. power supply and to ground for safety. The power supply is energized and a portion of the gas is ionized. The work pieces are heated to temperatures of approximately 650.degree. to 1100.degree. F. for ion-nitriding or to temperatures of approximately 1650.degree. to 1900.degree. F. for ion carburizing. The heating is effected at least in part by the ion activity but auxiliary heating elements may be used if desired.
    Type: Grant
    Filed: December 20, 1978
    Date of Patent: January 20, 1981
    Assignee: Abar Corporation
    Inventors: Rush B. Gunther, Prem C. Jindal
  • Patent number: 4225744
    Abstract: A fixedly mounted thermocouple for vacuum electric furnaces is described, which is particularly suitable for furnaces for nitrided or carburized case formation and which is particularly suited to avoid line of sight metallic deposition on the mounting from sputtering in the furnace and which could result in shorting, spaced shields being provided on the thermocouple mounting for this purpose.
    Type: Grant
    Filed: January 15, 1979
    Date of Patent: September 30, 1980
    Assignee: Abar Corporation
    Inventors: William R. Jones, Prem C. Jindal
  • Patent number: 4124199
    Abstract: A process and apparatus for case hardening of ferrous metal work pieces is described in which the work pieces to be processed are placed inside a metal vacuum chamber which is evacuated with a mechanical pump and then backfilled with a partial pressure of a gas containing nitrogen, such as nitrogen or ammonia, or a hydrocarbon such as methane, or mixtures thereof. The work pieces to be processed are electrically connected to the negative (cathode) terminal of a D.C. power supply, the positive terminal being connected to the chamber wall and to ground. The power supply is energized and some of the gas is converted to ions. The work pieces are heated to temperatures of approximately 650.degree. to 1100.degree. F for ionitriding or to temperatures of approximately 1650.degree. to 1900.degree. for ion carburizing. The heating is effected at least in part by the ion activity.
    Type: Grant
    Filed: July 11, 1977
    Date of Patent: November 7, 1978
    Assignee: Abar Corporation
    Inventors: William R. Jones, Prem C. Jindal