arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1309.2575cond-mat.mtrl-scicond-mat.mes-hall
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间隙硼固溶强化WB $_{3+x}$

Interstitial-Boron Solution Strengthened WB$_{3+x}$

Xiyue Cheng, Wei Zhang, Xing-Qiu Chen, Haiyang Niu, Peitao Liu, Kui Du, Gang Liu, Dianzhong Li, Hui-Ming Cheng, Hengqiang Ye, Yiyi Li

摘要:

采用密度泛函理论变组分进化算法,结合像差校正高分辨透射电镜实验,对WB $_{3+x}$($x$ $<$ 0.5)的组分、结构和硬度性能进行了研究和表征。我们提供了强有力的证据,化学计量WB $_3$和非化学计量WB $_{3+x}$的发生都在亚稳态$hP$ 16($P6_3/mmc$)结构结晶。没有形成备受争议的WB $_4$的迹象($hP$ 20和$hP$ 10)相的存在。我们的结果合理化了看似矛盾的高压实验结果,并提出间隙硼原子位于钨层中并与四个硼原子垂直互连,从而形成典型的三中心硼网,上下硼层形成三维共价网络,从而增强硬度。

英文摘要:

By means of variable-composition evolutionary algorithm coupled with density functional theory and in combination with aberration-corrected high-resolution transmission electron microscopy experiments, we have studied and characterized the composition, structure and hardness properties of WB$_{3+x}$ ($x$ $<$ 0.5). We provide robust evidence for the occurrence of stoichiometric WB$_3$ and non-stoichiometric WB$_{3+x}$ both crystallizing in the metastable $hP$16 ($P6_3/mmc$) structure. No signs for the formation of the highly debated WB$_4$ (both $hP$20 and $hP$10) phases were found. Our results rationalize the seemingly contradictory high-pressure experimental findings and suggest that the interstitial boron atom is located in the tungsten layer and vertically interconnect with four boron atoms, thus forming a typical three-center boron net with the upper and lower boron layers in a three-dimensional covalent network, which thereby strengthen the hardness.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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