Patents Assigned to Robert Zapp Werkstofftechnik GmbH & Co. KG
  • Process for the production of tools
    Patent number: 5028386
    Abstract: In a process for making tools from medium and high alloy steels or stellites by superplastic precision forming a powder metallurgically produced starting material with an equiaxed structure and more than 30% by volume of carbidic and/or boridic precipitated phase of particle size 1 to 0.2 .mu.m is given a matrix grain size of 1 to 3 .mu.m by thermomechanical processing (hot forming) and formed in the superplastic state.
    Type: Grant
    Filed: October 17, 1990
    Date of Patent: July 2, 1991
    Assignee: Robert Zapp Werkstofftechnik GmbH & Co. KG
    Inventor: Georg Frommeyer