Einfluss der chemischen Zusammensetzung und des pH-Wertes auf das Korrosionsverhalten von WC-Co Hartmetallen

Translated title of the contribution: Influence of the binder composition and pH-value on the corrosion behavior of (WC-Co) based cemented carbides.

Markus Unterlerchner

Research output: ThesisDiploma Thesis

796 Downloads (Pure)

Abstract

By potentiodynamic electrochemistry and immerson tests, the corrosion behaviour of (WC-Co) based cemented carbides has been investigated. The nickel contend of the binder (0 - 2%), the amount of the chromium carbide (0 - 1%) and the magnetic saturation (by adjustment of a carbon deficit, low high) have been varied. Also the pH-value of the chemical solution have been varied (pH 0, 3, 4.5, 6, 10 and 14). By TEM investigations the chemical composition of the binder has been determined. A very important parameter is the magnetic saturation. A high amount of dissolved tungsten depends on a low magnetic saturation. Tungsten protects the binder against corrosion in acids. At a higher pH-value the element tungsten has a bad influence on the corrosion behaviour. Nickel improves corrosion resistance at very low and very high pH-values. In neutrale solutions nickel yields to an increased corrosion rate due nickelous ions. Chromium improves has a very good influence on the behaviour from the pH-value 4 and higher.
Translated title of the contributionInfluence of the binder composition and pH-value on the corrosion behavior of (WC-Co) based cemented carbides.
Original languageGerman
QualificationDipl.-Ing.
Supervisors/Advisors
  • Mori, Gregor Karl, Supervisor (internal)
Award date14 Dec 2007
Publication statusPublished - 2007

Bibliographical note

embargoed until null

Keywords

  • Cemented carbides
  • corrosion
  • magnetic saturation
  • chromium carbide
  • Cr3C2
  • cobalt binder
  • nickel binder

Cite this