Twins enhanced mechanical properties of boron carbide

Boron carbide (B4C), an important structural ceramic with low toughness, is regarded as a potential bulletproof material for personnel and vehicles. Introducing twins into B4C ceramics may be one approach to achieving promising high mechanical properties. In this study, a single-phase B4C ceramic with a density close to the theoretical value was fabricated using homemade nano-powders via fast hot-pressing sintering (FHPS). The best sintering condition required holding at 2050 degrees C for 5 min. Sample synthesized under these conditions exhibited enhanced mechanical properties including a Vickers hardness of 32.2 GPa, fracture toughness of 4.18 MPa m1/2, and flexural strength of 486 MPa. Furthermore, transmission electron microscopy (TEM) analysis revealed that the sample was characterized by unusual high-density twins. The toughening mechanism of the obtained samples was investigated. These results demonstrate the importance of twin defects in improving mechanical properties for the development of high-performance B4C ceramics.

Automated summary

In this study, a single-phase B4C ceramic was fabricated using fast hot-pressing sintering, and it was found that the samples synthesized under the optimal sintering condition exhibited high mechanical properties, with twins playing a crucial role in toughening.