Patents by Inventor Ludwig Hachtel

Ludwig Hachtel 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).

  • Corrosion resistant steel structural member
    Patent number: 4919885
    Abstract: The invention relates to a structural steel having high resistance to intergranular stress operation cracking, more particularly in nitrate solutions and good welding properties (in % by mass):0.01 to 0.04% carbonup to 0.012% nitrogen0.08 to 0.22% titanium with Ti equal or greater than 3.5 (C+N)0.2 to 2.5% manganese2.0 to 5.5% chromium0.01 to 0.10% aluminiumup to 0.5% siliconup to 1.0% nickelup to 0.02% phosphorusup to 0.02% sulphurthe residue being iron and unavoidable impurities.
    Type: Grant
    Filed: September 28, 1988
    Date of Patent: April 24, 1990
    Assignee: Thyssen Stahl AG
    Inventors: Lutz Meyer, Ludwig Hachtel, Gunter Robusch