Combined Carburizing And Nitriding (e.g., Carbonitriding, Nitrocarburizing, Etc.) Patents (Class 148/218)
  • Patent number: 5232522
    Abstract: A process is disclosed for forming a coating on a substrate. A metal layer is placed onto the substrate either by plasma spray deposition or by applying a metal foil and then subjecting it to rapid omnidirectional compaction. The metal is then reacted with a source of carbon, nitrogen, or a combination thereof, such that a metal carbide, nitride, or carbonitride layer is formed. The product is a densified coated ceramic composition.
    Type: Grant
    Filed: October 17, 1991
    Date of Patent: August 3, 1993
    Assignee: The Dow Chemical Company
    Inventors: Stephen J. Doktycz, Kevin E. Howard
  • Patent number: 5154779
    Abstract: A method of nitriding an article of refractory-nitride-forming metal or metalloids. A consolidated metal or metalloid article is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid to an article of refractory nitride. in addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.
    Type: Grant
    Filed: February 18, 1992
    Date of Patent: October 13, 1992
    Assignee: Martin Marietta Energy Systems, Inc.
    Inventors: Cressie E. Holcombe, Norman L. Dykes, Terry N. Tiegs