Abstract This paper studies the microstructure and mechanical properties of hot pressed submicron TiB 2 powders obtained from a special carbon coated precursors method. With the hot press temperature increasing from 1500 °C to 1800 °C, the relative density increases and the sample maintains a single TiB 2 phase. The powders are able to be sintered to a relative density of ~94.5% at the temperature of 1800 °C. For the first time, unique elongated platelike grain structure, which has only been observed from transient liquid phase or reaction sintered borides, also forms at the sintering temperature of 1800 °C. In addition, the sample sintered at 1800 °C has a fine microstructure (elongated grain of ~0.3–3 µm) and high mechanical properties (hardness of ~27.6 ± 2.3 GPa, flexural strength of ~560 ± 49 MPa, and fracture toughness of ~6.5 ± 0.2 MPa m −1/2 ). Correlations between mechanical properties and microstructure are further discussed.

中文翻译：

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热压亚微米TiB 2 粉末的显微组织和力学性能

摘要 本文研究了通过特殊碳包覆前驱体方法获得的热压亚微米TiB 2 粉末的微观结构和力学性能。随着热压温度从 1500 °C 增加到 1800 °C，相对密度增加，样品保持单一的 TiB 2 相。在 1800 °C 的温度下，粉末能够烧结到~94.5% 的相对密度。首次在 1800 °C 的烧结温度下也形成了独特的细长板状晶粒结构，这种结构只能从瞬态液相或反应烧结硼化物中观察到。此外，在 1800 °C 下烧结的样品具有精细的微观结构（~0.3-3 µm 的细长晶粒）和高机械性能（~27.6 ± 2.3 GPa 的硬度，~560 ± 49 MPa 的弯曲强度和~6.5±0。2 兆帕米 -1/2 )。进一步讨论了机械性能和微观结构之间的相关性。