The New Complex High-entropy Metal Boron Carbonitride: Microstructure and Mechanical Properties

Abstract Dense (Ta, Nb, Hf, Zr, Ti)(BCN) ceramics (HEC-2) were successfully synthesized via hot-pressing sintering. Results show that sintering temperature and (BCN) addition have great impacts on the microstructure and mechanical properties of HEC-2 ceramics. The microstructure and phase of HEC-2 bulk ceramics were characterized by SEM, XRD and TEM. It was found that high-entropy phase, oxide phase and BN/C phase were precipitated when HEC-2119 powders were sintered at 1900 oC. In addition, the Vicker’s hardness, Bending strength, Bulk density and Open porosity of HEC-2319 ceramic are 24.54 GPa, 522.00 MPa, 9.07 g/cm3 and 0.05%, respectively, whose molar ratio of metal to (BCN) is 1: 0.334. In this work, BCN high-entropy ceramics were sintered on the basis of powder preparation, as provided that sintering temperatures and components have great influences on microstructure and mechanical properties of HEC-2 ceramics.