Patents by Inventor Anna H. Stigenberg

Anna H. Stigenberg 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).

  • Precipitation hardenable martensitic stainless steel
    Patent number: 5512237
    Abstract: Precipitation hardenable martensitic stainless steel of high strength combined with high ductility. The Iron-based steel comprises of about 10 to 14% chromium, about 7 to 11% nickel, about 0.5 to 6% molybdenum, up to 9% cobalt, about 0.5% to 4% copper, about 0.4 to 1.4% titanium, about 0.05 to 0.6% aluminium, carbon and nitrogen not exceeding 0.05% with iron as the remainder and all other elements of the periodic table not exceeding 0.5%.
    Type: Grant
    Filed: March 3, 1994
    Date of Patent: April 30, 1996
    Assignee: Sandvik AB
    Inventor: Anna H. Stigenberg