Full densification of zirconium carbide ceramics sintered under high pressure at low temperature

Zirconium carbide (ZrC) ceramic is one of the most important and promising materials with a high melting point. However, its low diffusion coefficient affects its densification behavior, which dramatically limits its engineering application. For polycrystal ceramic materials, sintering by thermal diffusion is the most widely used method for consolidation. But in view of the difficult densification behavior of ZrC, it is necessary to develop new sintering methods together with another driving force. In the study, we reported an ultra-high-pressure sintering strategy to fully densify ZrC ceramic under 1.7 GPa at 1600celcius. The sintered sample exhibited high density, fine grain size, excellent mechanical properties, and a large number of crystal defects, including dislocation networks and walls, which were similar to those in deformed metals. Its hardness increased to 2057.44 HV0.1 because of its unique microstructure.

Automated summary

An ultra-high-pressure sintering strategy was developed to fully densify ZrC ceramic under 1.7 GPa at 1600 degrees Celsius, resulting in high density, fine grain size, excellent mechanical properties, and a large number of crystal defects. This unique microstructure led to an increased hardness of 2057.44 HV0.1.