Patents by Inventor Karl Theodore Hartwig

Karl Theodore Hartwig 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: 5753380
    Abstract: The present invention concerns an aluminum alloy conductor of a cryostatic stabilizer for use at ultra low temperatures of 30.degree. K. or lower which is provided on and around a superconductor. The aluminum alloy conductor is made of 6 to 200 weight ppm of at least one element selected from the group of metallic and semimetallic effective elements consisting of B, Ca, Ce, Ga, Y, Yb and Th, and aluminum and inevitable impurities. The aluminum alloy conductor is obtained by adding at least one of these elements into a high purity aluminum whose purity is at least 99.98 wt. %. The aluminum alloy conductor has a 0.2% proof strength of not greater than 2.6 Kg/mm.sup.2.
    Type: Grant
    Filed: May 16, 1995
    Date of Patent: May 19, 1998
    Assignees: Sumitomo Chemical Co., Ltd., The Texas A&M University System
    Inventors: Akihiko Takahashi, Hitoshi Yasuda, Karl Theodore Hartwig, Lacy Clark McDonald
  • Patent number: 5733389
    Abstract: A method for manufacturing an aluminum alloy conductor for use at ultra low temperature which involves the steps of adding at least one of the metallic and semimetallic effective elements selected from the group consisting of B, Ca, Ce, Ga, Y, Yb and Th, in a total amount of 6 to 200 weight ppm, into a previously prepared molten high purity aluminum having a purity of not less than 99.98 wt % to thereby obtain a molten metal mixture; casting the molten metal mixture to thereby obtain a casting; subjecting the casting to extrusion working at 150.degree. C. to 350.degree. C. in an area reduction ratio of 1:10 to 1:150 whereby an extrusion worked product is formed; and annealing the extrusion worked product at a temperature of 250.degree. C. to 530.degree. C. for 3 to 120 minutes, whereby an aluminum alloy conductor for use at ultra low temperature is obtained.
    Type: Grant
    Filed: May 18, 1995
    Date of Patent: March 31, 1998
    Assignees: Sumitomo Chemical Co., Ltd., Texas A & M University System
    Inventors: Akihiko Takahashi, Hitoshi Yasuda, Karl Theodore Hartwig, Lacy Clark McDonald