Patents by Inventor Nils A. hrberg

Nils A. hrberg 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: 4459162
    Abstract: A hot work steel with very high resistance to tempering and a very high strength at elevated temperatures, a good ductility and a comparatively low content of expensive alloying elements; the steel contains in weight percent: 0.30-0.45 C, 0.2-1.0 Si, 0.3-2.0 Mn, 2.0-3.5 Cr, 1.5-2.5 (W/2+Mo), 0.8-1.5 V, 0-0.01 B, balance essentially only iron and impurities in normal quantities; for a further embodiment the steel contains a maximum of 1.0, preferably a maximum of 0.5 and suitably a maximum of 0.3% cobalt; in the hardened and tempered condition the steel has a fine grain lath-martensitic or partly bainitic microstructure which is free from retained austenite, and which contains a very finely dispersed intergranular precipitation of carbides, among which vanadium carbides are the dominating carbide phase.
    Type: Grant
    Filed: August 26, 1982
    Date of Patent: July 10, 1984
    Inventors: Lars-Ake Norstrom, Nils A. hrberg