Patents by Inventor Paul D. Vawter

Paul D. Vawter 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 manufacturing powder metallurgical tooling
    Patent number: 5989483
    Abstract: A method of forming a refractory die, and a method for forming a metal article using a refractory die. The refractory die is formed of a ceramic material by casting a slurry containing particles of the ceramic material onto a mold. Then the mold is vibrated while excess liquid medium from the slurry is simultaneously removed, whereby ceramic particles continue to flow into surface details of the mold. The present method of forming a refractory die minimizes drying and firing shrinkage, and even adjusts for drying and firing shrinkage by inclusion of kyanite in the refractory die. According to the method of forming a metal article, a particulate material containing powdered metal is compressed on a refractory die at an elevated temperature and pressure. The consolidated particulate material is differentially cooled, wherein a first, low mass portion contacting the refractory die is cooled more quickly than an opposing, high mass portion of the consolidated body.
    Type: Grant
    Filed: January 9, 1998
    Date of Patent: November 23, 1999
    Inventor: Paul D. Vawter
  • Method for manufacturing powder metallurgical tooling
    Patent number: 5985207
    Abstract: A method of forming a refractory die, and a method for forming a metal article using a refractory die. The refractory die is formed of a ceramic material by casting a slurry containing particles of the ceramic material onto a mold. Then the mold is vibrated while excess liquid medium from the slurry is simultaneously removed, whereby ceramic particles continue to flow into surface details of the mold. The present method of forming a refractory die minimizes drying and firing shrinkage, and even adjusts for drying and firing shrinkage by inclusion of kyanite in the refractory die. According to the method of forming a metal article, a particulate material containing powdered metal is compressed on a refractory die at an elevated temperature and pressure. The consolidated particulate material is differentially cooled, wherein a first, low mass portion contacting the refractory die is cooled more quickly than an opposing, high mass portion of the consolidated body.
    Type: Grant
    Filed: April 21, 1997
    Date of Patent: November 16, 1999
    Inventor: Paul D. Vawter