Improved densification and hardness of high-entropy diboride ceramics from fine powders synthesized via borothermal reduction process
Improved densification and hardness of high-entropy diboride ceramics from fine powders synthesized via borothermal reduction process
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DOI：
10.1016/j.ceramint.2020.02.214
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发表时间：
2020-06
影响因子：
5.2
通讯作者：
Yan Zhang;Shikuan Sun;Wei Zhang;Y. You;Wei‐Ming Guo;Zhi-Wei Chen;Jinhai Yuan;Hua-Tay Lin
中科院分区：
文献类型：
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作者：
Yan Zhang;Shikuan Sun;Wei Zhang;Y. You;Wei‐Ming Guo;Zhi-Wei Chen;Jinhai Yuan;Hua-Tay Lin
采用1600℃硼热还原粉末合成和2000℃氩气放电等离子烧结相结合的方法制备了（Zr0.2Ta0.2Ti0.2Nb0.2Hf0.2） b2和（Zr0.2W0.2Ti0.2Mo0.2Hf0.2） b2高熵硼化物陶瓷。高温还原后的高熵二硼化物粉末具有超细粒度（<0.5 μm）。烧结后得到了单相的（Zr0.2Ta0.2Ti0.2Nb0.2Hf0.2） b2陶瓷。然而，在（Zr0.2W0.2Ti0.2Mo0.2Hf0.2） b2陶瓷中检测到具有标称WB成分的小相。（Zr0.2W0.2Ti0.2Mo0.2Hf0.2） b2陶瓷具有较高的相对密度和27.7 GPa的硬度，高于（Zr0.2Ta0.2Ti0.2Nb0.2Hf0.2） b2陶瓷（相对密度94.0%，硬度16.4 GPa）或其他高熵硼化物陶瓷（相对密度~92%，硬度17.5 ~ 23.7 GPa）的测量值。
High-entropy boride ceramics of (Zr0.2Ta0.2Ti0.2Nb0.2Hf0.2)B2and (Zr0.2W0.2Ti0.2Mo0.2Hf0.2)B2were prepared by combining powder synthesis via borothermal reduction process at 1600 °C and subsequent ceramic densification by spark plasma sintering at 2000 °C in argon. High-entropy diboride powdered products exhibited ultra-fine particle size (<0.5 μm) after borothermal reduction. (Zr0.2Ta0.2Ti0.2Nb0.2Hf0.2)B2ceramic with the single phase was obtained after sintering. However, the minor phase with the nominal WB composition was detected in (Zr0.2W0.2Ti0.2Mo0.2Hf0.2)B2ceramic. (Zr0.2W0.2Ti0.2Mo0.2Hf0.2)B2ceramic exhibited a high relative density associated with the high hardness of 27.7 GPa, which were higher than those measured for (Zr0.2Ta0.2Ti0.2Nb0.2Hf0.2)B2ceramics (94.0% in relative density and 16.4 GPa in hardness) or the reported values (~92% in relative densities and 17.5–23.7 GPa in hardness) of other high-entropy boride ceramics.