Interface character distributions in WC/Co cemented carbide

Abstract

Electron backscatter diffraction， five parameter analysis， overlap-pole-figure analysis and near coincident site analysis were used to investigate the interface character distributions of WC/WC grain boundaries and WC/Co phase boundaries in WC/Co cemented carbides under different heat treatment states. The results show that the WC/WC Σ2 grain boundaries with a fraction of 4.5% are generated in the oil-quenched sample after high temperature sintering. The fraction of Σ2 boundaries with interface matching features of ｛101¯0｝/｛101¯0｝ is 2.6%.The cobalt in this sample is basically face-centered-cubic structure， and the interface with the interface inter-connection features of ｛101¯0｝WC/｛001｝Co，｛101¯0｝WC/｛110｝Co and ｛112¯0｝WC/｛110｝Co is the main part of the WC/Co phase boundary. After tempering at 800 ℃， the samples with atmosphere protection and slow cooling in the furnace have the proportion and characteristics of WC/WC Σ2 grain boundaries， which are very close to those of oil-quenched samples.The cobalt in this sample is primarily hexagonal structure， and the interface with the interface inter-connection features of ｛101¯0｝WC/｛101¯0｝Co and ｛112¯0｝WC/｛112¯0｝Co is the main part of the WC/Co phase boundary.

Keywords

• wc/co cemented carbide
• electron backscatter diffraction
• interface character distribution
• grain boundary inter-connection