Quantitative energy-filtered transmission electron microscopy investigations of cermets

The carbon and nitrogen contents on a microscopic scale are relevant to the performance of a cermet cutting tool material. Consequently, to fully understand the behaviour of these materials it is important to be able to locate these elements with the methods available for microstructural characterization. In this paper, we evaluate energy-filtered transmission electron microscopy for the study of cermet materials. To demonstrate the potential of this technique the microstructure of a Ti(C, N)-TiN-WC-Co cermet, for which the sintering process was interrupted at different stages, has been studied. It was found that energy-filtered transmission electron microscopy can provide an excellent overview of the elemental distribution in the materials, even for light elements. Within a reasonable time the same amount of information cannot be provided by point analysis or any other method with the spatial resolution required. Data are presented as elemental maps, jump ratio images, quantitative elemental maps, RGB images and chemical phase maps. Advantages and limitations with the different ways of displaying data for cermet studies are discussed.