Patents by Inventor Tzolo Valkov Rashev

Tzolo Valkov Rashev 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).

  • Nickel-free austenitic corrosion-resistant steel
    Patent number: 4116683
    Abstract: A nickel-free corrosion-resistant steel which consists by weight of:Carbon .ltoreq. 0.08%Silicon .ltoreq. 0.9%Chromium = 18.05 to 22%Manganese = 6.0 to 10.5%Nitrogen = 0.40 to 1.10%Sulfur .ltoreq. 0.025%Phosphorus .ltoreq. 0.035%Copper .ltoreq. 3% and the remainder iron.
    Type: Grant
    Filed: April 25, 1977
    Date of Patent: September 26, 1978
    Assignee: Institute po Metaloznanie i Technologia na Metalite
    Inventors: Ivan Dimov Nikolov, Tzolo Valkov Rashev, Rangel Petrov Ivanov, Chavdar Andreev Andreev