Stainless steel and carbon steel composite, and method of producing the same
CA 2116144 C · Owner: Allegheny Ludlum Corporation · Inventors: Parayil, Thomas R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A pressure-bonded composite material includes at least one layer of a stabilized low carbon steel core material and one layer of a stainless steel joined at an interface wherein the stabilized carbon steel includes columbium and at least one other carbide-forming element in amounts effective to prevent carbon migration from the carbon steel to the stainless steel and the composite material has a physical grain size no larger than ASTM #6.
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 February 22, 1994 and granted May 1, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 22, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 22, 2016.
- 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.