Patents by Inventor Doru M. Stefanescu

Doru M. Stefanescu 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).

  • Method for producing shaped parts from high temperature oxide metal superconductive composites
    Patent number: 5145836
    Abstract: A technique which produces macroscopically homogeneous-shaped parts utilizes oxide-metal superconductor composites by providing a mixture of a superconductor oxide, a metal and either a oxygen or a fluorine donor.
    Type: Grant
    Filed: November 2, 1987
    Date of Patent: September 8, 1992
    Assignee: The University of Alabama
    Inventors: In-Gann Chen, Doru M. Stefanescu, Subhayu Sen, Joel Betts
  • Compacted graphite cast irons in the iron-carbon-aluminum system
    Patent number: 4501612
    Abstract: A process for the production of a compacted graphite cast iron which is substantially free of carbides in castings as thin as 0.15 inches, and with nodularities of less than 20% by volume without postinoculation, which comprises adding aluminum to a compacted graphite cast iron, such that the compacted graphite cast iron consists essentially of about 0.5 to 7% by weight aluminum, about 2.5 to 4% carbon, 0 to about 1.5% silicon, with the remainder iron and inevitable impurities.The compacted graphite cast iron produced thereby is useful in the production of castings with both thick and thin sections.
    Type: Grant
    Filed: October 27, 1983
    Date of Patent: February 26, 1985
    Assignee: The University of Alabama
    Inventors: Doru M. Stefanescu, Freddy Martinez
  • Manufacturing process of vermicular graphic cast-irons through double modification
    Patent number: 4246026
    Abstract: A two-stage method of making vermicular graphite cast iron in which a first alloy is introduced into the ladle into which the iron is cast and then the vermicular graphite level is measured. A second alloy of a compacting or anticompacting nature is then added to ensure a final vermicular graphite level of at least 85% of the total graphite.
    Type: Grant
    Filed: September 12, 1979
    Date of Patent: January 20, 1981
    Assignee: Institutul de Cercetari Stiintifice, Inginerie Tehnologica si Proiectari Pentru Sectoare Calde
    Inventors: Doru M. Stefanescu, Lucian Dinescu, Stefan Craciun, Ioan Cristea