Contribution of image analysis to solid state sintering of WC-Co
Laboratoire de Thermodynamique et Physico-Chimie Métallurgiques, ENSEEG domaine universitaire BP 75, 38402 St Martin d 'Hères Cedex, France
Laboratoire de Thermodynamique et Physico-Chimie Métallurgiques, ENSEEG domaine universitaire BP 75, 38402 St Martin d 'Hères Cedex, France
Abstract
Solid-state sintering of the WC-Co system has been studied by image analysis. Automatic phase segmentation and measurements were possible through the combination of optimized specimen preparation, high spatial resolution in S.E.M., and image processing in a software oriented image analyzer. Three phases could thus be extracted from the microstructure, the carbide phase (WC), the binder phase (Co) and the porous phase, in order to evaluate for each one classical stereological parameters like volume fraction or specific contact surfaces. As well, using mathematical morphology through measurements of chord length distribution and covariance, some major features of solid phase sintering of the WC-Co system could be characterized: quantitative and morphological evolution of porosity with sintering temperature, wetting of the carbide grains by the binder, rearrangement and shape accomodation processes.