Hard composite and method of making the same
CA 2229032 C · Owner: Kennametal Inc. · Inventors: Greenfield, Mark S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of heat treating a green compact having an exposed surface. The method includes the steps of: providing a green compact comprised of a hard carbide and binder; placing a powder of grain refiner on at least one portion of the exposed surface of the green compact; and heat treating the green compact and grain refiner powder so as to diffuse the grain refiner toward the center of the green compact thereby forming a peripheral zone (80) inwardly from the exposed surface in which the grain refiner was placed and forming an , interior zone (84). The peripheral zone having a grain size that is smaller than the grain size of the bulk zone.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed July 3, 1996 and granted November 27, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 3, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 3, 2018.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.