A study of mechanical properties of pure and nitrogen-doped ultrananocrystalline diamond films under various loading conditions

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:46

Article

Chen, Zhen^1,2,3 

[1] Monash Univ, Dept Civil Engn, Clayton, Vic 3800, Australia

[2] Univ Missouri, Dept Civil & Environm Engn, Columbia, MO 65211 USA

[3] Dalian Univ Technol, Fac Vehicle Engn & Mech, Dept Engn Mech, Dalian 116024, Peoples R China

关键词: Ultrananocrystalline diamond;    Molecular dynamics;    Grain boundaries;    N-Doping;    Size effect;    Rate effect;    Temperature effect;   

DOI  :  10.1016/j.ijsolstr.2008.09.036

来源: Elsevier

【 摘 要 】

To better understand the mechanical responses of ultrananocrystalline diamond (UNCD) under various loading conditions, a numerical study is performed to investigate the size, loading rate and temperature effects on the material properties of pure and nitrogen-doped UNCD films. Since the UNCD growth mechanism is not completely understood yet, a simple procedure by combining kinetic Monte Carlo and molecular dynamics (MD) methods is developed to form a polycrystalline UNCD block with an artificial grain boundary (GB). By randomly inserting different numbers of nitrogen IN) atoms into the GB of the resulting polycrystalline UNCD films, N-doped UNCD films can be formed. The responses of the simulated pure and N-doped UNCD films with various grain sizes are then investigated by applying displacement-control led tensile loading under different rates and temperatures in the MD simulations. The simulation results presented in this paper provide a better understanding of the combined size, rate and thermal effects on the material responses of pure and N-doped UNCD films. (c) 2008 Elsevier Ltd. All rights reserved.

【 授权许可】

Free