Patents Represented by Attorney Francis C. McAulay Fisher Nissen Goldberg & Kiel Hand
  • Patent number: 5482672
    Abstract: The process for extruding tantalum or niobium includes sealing a cold isostatically pressed charge of tantalum or niobium powder in a first metal cylinder and then sealing the first cylinder in a second metal cylinder with a metal powder of spherical shape in a gap between the cylinders. Thereafter, the second cylinder is cold isostatically pressed to prevent the metal powder in the gap from segregating. This is followed by heating and extrusion of the second container to form, e.g. an extruded bar. The ends of the bar and the skin on the bar can be removed to obtain a rod of tantalum (or niobium) with a yield of from 95% to 96% of the original powder.
    Type: Grant
    Filed: February 9, 1995
    Date of Patent: January 9, 1996
    Inventors: Ira Friedman, Christer Aslund