Failure analysis of WC-3.5wt%Co cemented carbides in mining Applications

Abstract

In order to further understand the wear mechanisms of cemented carbide cutter head of conical pick, six wornout cutter heads were investigated detailedly through scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). Abrasion wear and tipping were found to be the main wear mechanisms of the worn out cutter heads. Thermal stress and impact load played important roles in the wearing process of cutter heads. The intermixed mineral particles in the worn out areas aggravated the wear on the surface of cemented carbide. The spherical particles and vine-like structures were found to distribute in the wornout areas arbitrarily, and the compositions of which were detected using EDS.

Keywords

cemented carbide / abrasion wear / tipping / thermal stress / plastic deformation

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