Nanocomposite TiC-TiB₂ Powders by SHS through Metastability Approach

Abstract

The aim of this work is the achievement of nanostructured TiC–TiB2 powders through a metastability approach based on the Self–propagating High–temperature Synthesis (SHS) process followed by quench to obtain highly metastable powder agglomerates. An optimisation of the reaction stoichiometry was carried out in order to obtain products with approximately eutectic composition (i.e. 67%mol TiC – 33%mol TiB2). An optimized amount of sodium borate was used as gasifying additive to produce dispersed nanostructured powder agglomerates. The metastability of the nanocomposite powders obtained through the (SHS+quench) route was evaluated by annealing. The morphological evolution of the powders after thermal treatment yielded a recrystallisation with limited grain growth of the nanostructured TiC–TiB2 phases and demonstrated the metastability of the products obtained by the (SHS+quench) route.

Fabrication and Characterisation of Nanostructured Coatings by Magnetron Sputtering for Wear Resistant Applications

“…Self-propagating High-temperature Synthesis (SHS) [12] offers a simple and efficient alternative route for the production of composite targets to be employed in sputtering of composite thin films. Carbides and borides of transition metals are refractory materials that can be easily synthesised by SHS [13] and offer considerable potentials for the fabrication of both thermally and chemically stable coatings [14]. Composite materials with accurately controlled compositions suitable as targets for sputtering can be produced by SHS.…”