Patents by Inventor Klaus Freier

Klaus Freier 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).

  • Patent number: 6749696
    Abstract: The production of a cold-rolled strip or sheet of steel with good deforming properties, which is subjected to recrystallizing annealing and, if appropriate, a dressing operation after hot rolling, coiling and cold rolling and has a bake-hardening potential after a subsequent deformation and for a subsequent temperature treatment, succeeds because the recrystallizing annealing is carried out in a bell-type furnace while coiled and because the strip or sheet is subjected to cooling at a cooling rate of ≧1° C./s after the recrystallizing annealing from a temperature T of 200° C.≦T≦A1. It is consequently possible to obtain properties of bell-annealed steels and nevertheless attain a bake-hardening effect, in particular for C contents of ≧0.02%.
    Type: Grant
    Filed: January 23, 2002
    Date of Patent: June 15, 2004
    Assignee: Salzgitter AG
    Inventors: Klaus Freier, Volker Flaxa, Birgit Reichert
  • Publication number: 20030145919
    Abstract: The production of a cold-rolled strip or sheet of steel with good deforming properties, which is subjected to recrystallizing annealing and, if appropriate, a dressing operation after hot rolling, coiling and cold rolling and has a bake-hardening potential after a subsequent deformation and for a subsequent temperature treatment, succeeds because the recrystallizing annealing is carried out in a bell-type furnace while coiled and because the strip or sheet subjected to cooling at a cooling rate of ≧1° C./s after the recrystallizing annealing from a temperature T of 200° C. ≦T≦A1.
    Type: Application
    Filed: January 23, 2002
    Publication date: August 7, 2003
    Inventors: Klaus Freier, Volker Flaxa, Birgit Reichert
  • Patent number: 5139580
    Abstract: In order to produce sheet possessing good forming properties, in particular for rotationally symmetrical deep-drawings, a low-carbon steel containing not more that 0.009% N is alloyed with 0.01 to 0.94% Ti and in certain cases with 0.01 to 0.06% Nb and continuously cast. The plate slabs are heated to a temperature above 1120 degrees Celsius, rolled to obtain a hot strip above the Ar.sub.3 point, and would at 520.+-.100 degrees Celsius. After cold rolling to the desired fine sheet thickness, the steel strip is annealed by recrystallizaiton, skin-passes and made into sheets.
    Type: Grant
    Filed: July 18, 1990
    Date of Patent: August 18, 1992
    Assignee: Stahlwerke Peine-Salzgitter AG
    Inventors: Klaus Freier, Walter Zimnik
  • Patent number: 4397697
    Abstract: An improved method for the manufacture of hot strips or heavy plates from a denitrated steel composed of 0.04 to 0.16% carbon, 1.25 to 1.90% manganese, 0.2 to 0.55% silicon, 0.004 to 0.020% phosphorus, 0.002 to 0.015% sulfur, 0.02 to 0.08% aluminum, 0.02 to 0.08% niobium, the remainder iron and possibly contaminants, including the steps of having the hot strips or plates leaving the last finishing stand of rolls at a temperature of 750.degree. C. to 820.degree. C., cooling the hot strips or plates to an intermediates temperature of 450.degree. C. to 500.degree. C. at a cooling rate of 2.degree. to 10.degree. C./s and then slowly cooling the hot strips or plates in air to room temperature in a coil or in a pile.
    Type: Grant
    Filed: December 3, 1980
    Date of Patent: August 9, 1983
    Assignee: Stahlwerke Peine-Salzgitter AG
    Inventors: Klaus Freier, Constantin M. Vlad, Klaus Hulka