Patents by Inventor Sung S. Pak

Sung S. Pak 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: 5716671
    Abstract: A method for coating ceramic fibers such as Al.sub.2 O.sub.3 fibers includes immersing the Al.sub.2 O.sub.3 fibers in a polyelectrolyte solution. After the polyelectrolyte is allowed to adsorb on the fibers, the unabsorbed polyelectrolyte is washed from the fibers with a distilled water. The fibers are then deposited in an oxide solution such as SnO.sub.2. The SnO.sub.2 is allowed to adsorb on the fibers, and then the unabsorbed SnO.sub.2 is washed from the fibers with the distilled water. The fibers are then sintered at a temperature ranging from 400.degree. C. to 1200.degree. C.
    Type: Grant
    Filed: June 2, 1994
    Date of Patent: February 10, 1998
    Assignee: The Babcock & Wilcox Company
    Inventors: Sung S. Pak, Richard W. Goettler, Archie N. Tolley
  • Patent number: 5670103
    Abstract: A method of making ceramic fibers from a water soluble pre-ceramic polymer solution by forming fibers from a water soluble pre-ceramic polymer solution, drying the formed fibers at a first temperature ranging between 600.degree. C.-750.degree. C. at a temperature heating rate of about 1.degree. C. per minute. Next, raising the first temperature to a second temperature ranging from 800.degree. C.-1000.degree. C. at about 5.degree. C. per minute, and increasing the second temperature to still a third temperature of about 1200.degree. C. at about 10.degree. C. per minute and holding at the third temperature for about 1 hour. Finally, the fibers are cooled to room temperature at a rate of about 5.degree. C. to 30.degree. C. per minute.
    Type: Grant
    Filed: November 21, 1995
    Date of Patent: September 23, 1997
    Assignee: The Babcock & Wilcox Company
    Inventors: Sung S. Pak, Archie N. Tolley
  • Patent number: 5637175
    Abstract: The present invention generally relates to manufacturing apparatus for forming an integral three-dimensional object from individually contoured laminations of the same or gradually varying shape, successive laminae of that object being produced out of thin sheet or powder based materials through the cutting, fusing or physicochemical property changing action generated by a computer directed beam of concentrated energy or matter, successive substantially planar laminations of that object being automatically stacked together for step-wise laminar buildup of the desired three-dimensional object.
    Type: Grant
    Filed: October 7, 1994
    Date of Patent: June 10, 1997
    Assignee: Helisys Corporation
    Inventors: Michael Feygin, Sung S. Pak
  • Patent number: 5507986
    Abstract: An improved method of making a ceramic tube includes preparing a tube from ceramic fibers with filament winding. The tube is impregnated with a pre-ceramic water soluble polymer solution. The impregnated tube is dried and heated to a temperature of about 500.degree. C. with the impregnating and heating steps being repeated.
    Type: Grant
    Filed: September 16, 1994
    Date of Patent: April 16, 1996
    Assignee: The Babcock & Wilcox Company
    Inventors: Sung S. Pak, Archie N. Tolley
  • Patent number: 5437852
    Abstract: A method of making water soluble pre-ceramic polymers includes heating hydrated metal salts above their melting points. A flow of air drives off water and most of the ligands. Polymerization occurs in the melt and the remaining side groups make the polymer soluble in water. Solubilization in water is accomplished by mixing the polymer with distilled water and heating the mixture at a temperature higher than about 60.degree. C. Thus prepared polymer solutions may be used to form fibers, films, and composite matrices.
    Type: Grant
    Filed: May 13, 1993
    Date of Patent: August 1, 1995
    Assignee: The Babcock & Wilcox Company
    Inventors: Sung S. Pak, Archie N. Tolley
  • Patent number: 5352642
    Abstract: A method for fabricating Y.sub.3 Al.sub.5 O.sub.12 (YAG) fibers from water soluble polymers includes a pre-YAG polymer synthesis, with solution viscosity adjustment followed by fiber spinning and heat treatment. The polymer synthesis employs polar solvents such as water or alcohol with a carboxylic acid containing at least two carboxyl groups.
    Type: Grant
    Filed: November 10, 1992
    Date of Patent: October 4, 1994
    Assignee: The Babcock & Wilcox Company
    Inventors: Sung S. Pak, R. Allen Kimel