Patents by Inventor Dhirajlal C. Shah

Dhirajlal C. Shah 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).

  • Coated silicon nitride cutting tool and process for making
    Patent number: 4640693
    Abstract: A coated ceramic silicon nitride cutting tool comprises a substrate having a major portion by volume silicon nitride, a coating of refractory material thereon, and an interfacial layer intermediate between the substrate and the layer of refractory material. The interfacial layer comprises a refractory metal chemically reacted to form a reaction bonded refractory metal nitride for enhancing the adherence of the layer of refractory metal material to the substrate. The interfacial layer is provided by reacting a refractory metal halide with the surface to form a reaction bonded refractory metal nitride.
    Type: Grant
    Filed: April 15, 1985
    Date of Patent: February 3, 1987
    Assignee: GTE Valeron
    Inventors: Deepak G. Bhat, Dhirajlal C. Shah, John R. Kyle, Paul F. Woerner