TRIBOLOGICAL EVALUATION OF ULTRAFINE Ti(CN) CERMETS

Abstract

High temperature wear performance of ultrafine and coarse grade Ti(CN)-WC -Ni cermets was investigated by surface profilometry, atomic force microscopy, and scanning electron microscopy to ascertain the contribution of particle size effect. The observed wear depths, produced during wear test, showed direct correlation with the surface roughness, which in turn is controlled by the microstructural features. The cermets with ultrafine Ti(CN) exhibit greater homogeneity along with a considerably higher rim fraction in the typical core-rim microstructure when compared to its coarse counterpart. The improved microstructure accounts for the enhanced tribological properties in the ultrafine cermets.

Effect of Processing Routes on Physical & Mechanical Properties of Advanced Cermet System

“…Titanium carbonitrides based cermet's are considered as candidate materials for machining purposes in the tool industry, because they possess high mechanical properties and high wear performance [1,2].…”

GI-XRD studies on surface structure of ultrafine Ti(C0.5N0.5)-WC-Ni cermets at high temperature

“…The cores are the undissolved Ti(CN) while the rim comprises of solid solution of Ti(CN), secondary carbides and binder. Recent studies on sintered Ti(C 0.5 N 0.5 )-WC-Ni cermets have shown that the incorporation of ultrafine Ti(C 0.5 N 0.5 ) particles to the pre-sintered powder mix enhances the tribo-mechanical properties over coarse grade cermets [8][9][10]. This was attributed to a much better distribution of hard phases in the microstructure of as-sintered ultrafine cermet, apart from an improved lattice coherency.…”

Tomography Using the Transmission Electron Microscope

“…The latter requires accurate measurement of the magnetic induction and this can be achieved with a 3D form of electron holography [22]. Indeed, three-dimensional analysis will also become increasingly important not only for functional materials but also for nanoscale structural and engineering materials, such as ultra-fine cermets [23]. In the catalysis industry, heterogeneous catalysts [24] are now designed with nanometre-sized active particles distributed in three dimensions on or within a porous support structure-the tomography of such catalysts will be discussed later in the chapter.…”