B4C/metal boride composites derived from B4C/metal oxide mixtures

Microstructure, Thermo-Physical, Mechanical and Wear Properties of in-Situ Formed Boron Carbide - Zirconium Diboride Composite

“…This reactive sintering has been reported to enhance the sintering kinetics; as a result, it lowers the effective densification temperature. Goldstein et al [23] [3,23].…”

“…The resulting chemical reactions during sintering not only enhances the densification but also improves the thermo-mechanical and physical properties of dense bodies via the formation Ceramics -Silikáty 62 (1) 15-30 (2018) of reaction products such as carbides or borides [3,19,22,23]. The in-situ reaction of B 4 C with Me oxides (Me = Ti, Zr, Cr, V, Hf, Eu, La, and Y) yielded high dense B 4 C based composites (B 4 C-MeB 2 composites) at a lower sintering temperatures with improved mechanical properties compared to monolithic boron carbide [3,19,22,23]. It is reported that TiO 2 addition to B 4 C has helped to enhance the densification, due to the formation of sub-stoichiometric B 4 C by reactive sintering [19,24].…”

Competition between densification and microstructure development during spark plasma sintering of B4C–Eu2O3

“…High degree of covalency, low self‐diffusivity, high melting temperature and existence of surface oxide layer on nonoxide powder particles contribute to poor sinterability of boron carbide . Since the work by Skorokhod et al, there have been considerable research efforts are invested towards the use of different oxide systems as sinter additives to B 4 C . Oxide systems are thermally unstable with B 4 C and forms nonvolatile compounds (carbides/borides) in situ as reinforcement phase in ceramic matrix .…”

“…Oxide systems are thermally unstable with B 4 C and forms nonvolatile compounds (carbides/borides) in situ as reinforcement phase in ceramic matrix . Oxide additive‐based approach of processing boron carbide was reported to yield highly dense ceramic component at lower sintering temperatures, compared to monolithic boron carbide . Such ceramics exhibit fine grain microstructures and superior mechanical properties, when compared to monolithic boron carbide.…”

Synthesis of Boron Carbide by Reactive‐Pulsed Electric Current Sintering in the Presence of Tungsten Boride

“…Three main groups of sintering additives can be outlined based on their chemical composition: carbon or C — generating sources, transition metal (IV‐VI gr.) oxides, or borides . In previous works, high‐density B 4 C–W 2 B 5 materials with improved mechanical, electrical, and neutron‐absorption properties, compared to hot‐pressed B 4 C, have been obtained by reactive sintering of B 4 C at 2250°C in the presence of WC additives .…”