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Investigation of (Mo,W)C Mixed Carbides by Electron Probe Microanalysis and Kossel Technique

  • Hans-Jürgen Ullrich
  • Siegfried Rolle
  • Andreas Uhlig
  • Peter Ettmayer
  • Benno Lux
Part of the Mikrochimica Acta book series (MIKROCHIMICA, volume 10)

Abstract

Tungsten as an element has such a unique combination of outstanding properties that it is very difficult to find a substitute with similar properties. In alloys the task is somewhat simpler: tungsten in high speed steels has been successfully replaced at least partially by molybdenum in the past decades. Attempts to replace tungsten by molybdenum in the hardmetal industry, which takes up more than 50% of the total tungsten production, have been discouraged for a long time by the belief that molybdenum in hardmetal is harmful because of its tendency to form brittle subcarbide (Mo2 C)-needles or brittle complex compounds. It was only recently that Rudy and coworkers1 showed that tungsten atoms in WC can be replaced by molybdenum atoms without changing the crystal structure. Apparently a partial substitution of W in WC by Mo results in only gradual and minor changes in physical and mechanical properties. Hardmetals sintered with these mixed (Mo, W)C-carbides show nearly the same properties as straight WC-based hardmetals. The microstructure of Mo-substituted (Mo, W)C-Co hardmetals is distinctly different from that of unalloyed conventional WC-Co hardmetals. In (Mo, W)C-Co hardmetals the carbide grains have a zoned structure, which is easily observable in the etched microsection shown in Fig. 1. In order to gather further information on the homogeneity of composition and crystal structure within one single carbide grain, a combination of electron microprobe analysis (EPMA) and microbeam diffraction technique had to be employed.

Keywords

Tungsten Carbide Electron Probe Microanalysis High Speed Steel Outer Zone Molybdenum Carbide 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Springer-Verlag Wien 1983

Authors and Affiliations

  • Hans-Jürgen Ullrich
    • 1
  • Siegfried Rolle
    • 1
  • Andreas Uhlig
    • 2
  • Peter Ettmayer
    • 3
    • 4
  • Benno Lux
    • 3
  1. 1.Department of Material ScienceTechnical University of DresdenGerman Democratic Republic
  2. 2.Department of Mathematical CyberneticsTechnical University of DresdenGerman Democratic Republic
  3. 3.Institute for Chemical Technology of Inorganic MaterialsTechnical University of ViennaAustria
  4. 4.Institut für chemische Technologie anorganischer StoffeTechnische Universität WienWienAustria

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