正二十面体金刚石的形成及其计算机模拟

余志明; 魏秋平; 叶 浚; A. Flodrstrom

正二十面体金刚石的形成及其计算机模拟

中南大学材料科学与工程学院,湖南长沙 410083;
粉末冶金国家重点实验室,湖南长沙 410083;

基金项目: 粉末冶金国家重点实验室开放基金（2008112048）；湖南省研究生创新基金（134374236000005）；中南大学优秀博士论文扶持基金 (2008yb015) ；中南大学贵重仪器开放共享基金（ZKJ2008001）.

详细信息

作者简介:
余志明(1956-),男,湖南桃源人,瑞典皇家工学院博士,教授,博士生导师,主要从事化学气相沉积金刚石膜的研究.

中图分类号: O 613.71; TQ 163
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出版历程
- 收稿日期: 2008-05-10
- 录用日期: 2009-11-09
- 修回日期: 2008-12-30
- 刊出日期: 2009-06-20

Formation of an icosahedral diamond crystal and its computer simulation

School of Materials Science and Engineering, Central South University, Changsha 410083, China|
State Key Laboratory for Powder Metallurgy, Changsha 410083, China|

Funds: Open Fund of State Key Laboratory of Powder Metallurgy (2008112048); Innovation Foundation for Postgraduate of Hunan Province of China (1343-74236000005); Excellent Doctor Degree Thesis Support Foundation of Central South University (2008yb015); Open Fund for Valuable Instrument of Central South University (No.ZKJ2008001).

More Information

Author Bio:
YU Zhi-ming (1956-), male, Ph,D.of Royal Institute of Technology, Sweden, Professor, engaged in the research on CVD diamond film. Email: zhiming@mail.csu.edu.cn

摘要

摘要: 采用热丝化学气相沉积（HFCVD）法,以甲烷和氢气为反应气体,在YG13（WC13%Co）硬质合金基体上制备了金刚石膜。膜中存在大量五重对称结构的正二十面体金刚石晶粒（IDC）。当尺寸较小时晶粒为较完整的正二十面体形状,尺寸达微米级后晶粒为带有“沟槽”或“凹坑”的变种正二十面体形状。研究了IDC的形成机制,并进行了计算机模拟。结果表明：对于四面体立方结构来说,IDC的{111}孪晶面与正常{111}孪晶面相比存在2.87^o的差异,孪晶面两侧原子几何位置失配,使其成为畸变孪晶面,这种畸变孪晶面导致IDC晶粒存在“凹坑”和“沟槽”；IDC的晶核是正十二面体烷（C₂₀H₂₀）。
- O 613.71 /
- TQ 163
Abstract: Icosahedral diamond crystals (IDCs) were found in chemical vapour deposited diamond by a field emission scanning electron microscope, using. YG13 (cemented tungsten carbide containing 13% of Co) as a substrate. It is found that the nanometer sized IDCs are in the shape of a nearly perfect icosahedron and the micrometer sized IDCs are in the shape of a icosahedron with dimples or grooves. A simulation on atomistic scale is performed by assuming a nucleation-growth model in order to elaborate the mechanism of IDC formation. Results show that the nucleus of IDCs is dodecahedrane, C₂₀H₂₀. For the tetrahedral cubic packing, the dihedral angle of {111} facets of IDCs is 2.87^o larger than that of the normal {111} twin plane. The geometric position of the bilateral atoms on the {111} twin plane of IDCs is mismatched, resulting in a distorted twin plane (DTP) in IDCs. The high energy of DTP induces the dimples or grooves that occurred in IDCs.
- CVD /
- Diamond