Microstructure and mechanical properties of B4C densified by spark plasma sintering with Si as a sintering aid

Effects of ZrB2 contents on the mechanical properties and thermal shock resistance of B4C–ZrB2 ceramics

“…All hot-pressed B 4 C-ZrB 2 samples achieve nearly full densification. Owing to its strong covalent bonding and low self-diffusion coefficient, monolithic B 4 C ceramic is always hard to achieve full densification and is reported to be densified above 2100°C [6,7]. The introduction of appropriate second phase particle is proved to be an efficient method to improve the sinterability.…”

“…Despite of attractive application properties of B 4 C, its applicability mainly limits to its poor sinterability [6,7] and low fracture toughness [8,9]. The poor sinterability of B 4 C is mainly due to the strong covalent bonding and low self-diffusion coefficient.…”

“…The poor sinterability of B 4 C is mainly due to the strong covalent bonding and low self-diffusion coefficient. Usually, fully dense monolithic B 4 C ceramics without any use of additives need to be sintered above 2100°C through hot-pressing technique [6,7]. However, high temperature processing is very costly and usually induces significant grain coarsening and poor mechanical properties.…”

Demonstrating low‐temperature sintering of boron carbide powders

“…As compared in Table , this reactive sintering with in situ carbothermal reduction of B 4 C at ~1250 to 1400°C without pressurization resulted in low relative densities (57.7%‐62.8%), but these densities are comparable with those of pressureless sintering conducted at much higher temperatures (>2000°C) when no additives were introduced. While the papers reviewed in Table are limited to densification of monolithic B 4 C powders, densification with additives has been studied to increase densification: hydrogen and carbon to reduce oxygen or B 2 O 3 , and liquid phases (Si, Cr 3 C 2 , and Al) to enhance densification at lower temperatures.…”

High temperature flexural strength of B4C–ZrB2 ceramic at 1000–1600 °C in air

“…However, low strength of B 4 C is the major application impediment [4][5][6]. Moreover, due to its very strong covalent bonds, high resistance to grain interface sliding and lack of plasticity, densification of B 4 C is extremely difficult and costly [7][8][9].…”