One-step synthesis of high-entropy diborides with hierarchy structure and high hardness via aluminum-melt reaction method
Jinfeng Nie, Yating Zhi, Yong Fan, Yonghao Zhao, Xiangfa Liu
Abstract
Two new high-entropy metal diborides (ZrTiVCr)B 2 and (ZrTiVCrMn)B 2 were successfully synthesized via a novel aluminum melt reaction method.The high-entropy diboride crystals have a hexagonal structure and possess high compositional uniformity.We unexpectedly found that the Mn elements could significantly change the crystal morphology of (ZrTiVCrMn)B 2 , resulting in a hierarchically structured nanosheet-assembled nanoplatelet shape.Benefiting from this interesting hierarchical structure and enhanced lattice distortion, the average hardness of the (ZrTiVCrMn)B 2 phase is significantly enhanced to 31.44 GPa as compared to that of (ZrTiVCr)B 2 for 28.82 GPa.This work will supply a new paradigm for synthesizing high-entropy metal diborides.