Stacking-fault structure explains unusual elasticity of nanocrystalline diamonds

Tanei, Hiroshi; Tanigaki, Kenichi; Kusakabe, Koichi; Ogi, Hirotsugu; Nakamura, Nobutomo; Hirao, Masahiko

doi:10.1063/1.3077124

Cited by 18 publications

(15 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, our results seem to be in general agreement with measurements of Tanei et al, 13,14 who found an increase of Poisson's ratio for decreasing grain size and an increasing sp 2 bonded carbon content.…”

Section: Resultssupporting

confidence: 93%

“…Brillouin light scattering measurements by Jiang et al 10 the gas phase of the hot filament CVD, while Poisson's ratio of nanocrystalline diamond was found to increase up to 0.18 after addition of 0.5% N 2 to the gas phase. 13,14 In a simple approach the Poisson's ratio can be measured by the change of the width of a beam during elongation. 15 This approach is relatively inaccurate; especially in the case where Poisson's ratio is small, such as for diamond.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Young's modulus, fracture strength, and Poisson's ratio of nanocrystalline diamond films

Mohr

Caron

Herbeck-Engel

et al. 2014

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

Section: Resultssupporting

confidence: 93%

mentioning

confidence: 99%

Young's modulus, fracture strength, and Poisson's ratio of nanocrystalline diamond films

Mohr

Caron

Herbeck-Engel

et al. 2014

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…In principle, the deterioration of the stiffness is not surprising for an increase of the average interplane distance, while the Poisson ratio increases with an increase in the volume fraction of defects, but the simple model cannot reproduce these changes quantitatively. 60 Owing to the very large variety of possible morphologies and nanostructures, the relationship between microscopic structure and mechanical properties is still an open issue. This is true, especially, for NCD and UNCD diamond with strongly extended grain boundaries.…”

Section: E Nanocrystalline Diamondmentioning

confidence: 99%

The mechanical properties of various chemical vapor deposition diamond structures compared to the ideal single crystal

Hess

2012

Journal of Applied Physics

111

View full text Add to dashboard Cite

Bias-enhanced nucleation and growth processes for improving the electron field emission properties of diamond films J. Appl. Phys. 111, 053701 (2012) Direct visualization and characterization of chemical bonding and phase composition of grain boundaries in polycrystalline diamond films by transmission electron microscopy and high resolution electron energy loss spectroscopy Appl. Phys. Lett. 99, 201907 (2011) Impurity impact ionization avalanche in p-type diamond Appl. Phys. Lett. 99, 202105 (2011) Ultrathin ultrananocrystalline diamond film synthesis by direct current plasma-assisted chemical vapor deposition J. Appl. Phys. 110, 084305 (2011) Diamond nanoparticles with more surface functional groups obtained using carbon nanotubes as sourcesThe structural and electronic properties of the diamond lattice, leading to its outstanding mechanical properties, are discussed. These include the highest elastic moduli and fracture strength of any known material. Its extreme hardness is strongly connected with the extreme shear modulus, which even exceeds the large bulk modulus, revealing that diamond is more resistant to shear deformation than to volume changes. These unique features protect the ideal diamond lattice also against mechanical failure and fracture. Besides fast heat conduction, the fast vibrational movement of carbon atoms results in an extreme speed of sound and propagation of crack tips with comparable velocity. The ideal mechanical properties are compared with those of real diamond films, plates, and crystals, such as ultrananocrystalline (UNC), nanocrystalline, microcrystalline, and homo-and heteroepitaxial single-crystal chemical vapor deposition (CVD) diamond, produced by metastable synthesis using CVD. Ultrasonic methods have played and continue to play a dominant role in the determination of the linear elastic properties, such as elastic moduli of crystals or the Young's modulus of thin films with substantially varying impurity levels and morphologies. A surprising result of these extensive measurements is that even UNC diamond may approach the extreme Young's modulus of singlecrystal diamond under optimized deposition conditions. The physical reasons for why the stiffness often deviates by no more than a factor of two from the ideal value are discussed, keeping in mind the large variety of diamond materials grown by various deposition conditions. Diamond is also known for its extreme hardness and fracture strength, despite its brittle nature. However, even for the best natural and synthetic diamond crystals, the measured critical fracture stress is one to two orders of magnitude smaller than the ideal value obtained by ab initio calculations for the ideal cubic lattice. Currently, fracture is studied mainly by indentation or mechanical breaking of freestanding films, e.g., by bending or bursting. It is very difficult to study the fracture mechanism, discriminating between tensile, shear, and tearing stress components (mode I-III fracture) with these partly semiquantitative methods. A nov...

show abstract

“…Nanocrystalline diamond films grown under different growth conditions can exhibit similar average grain sizes but rather different elastic properties which also affect the thermal properties . Also the thermal conductivities of nanocrystalline diamond films show a wide range .…”

Section: Introductionmentioning

confidence: 99%

Thermal conductivity of nanocrystalline diamond films grown by hot filament chemical vapor deposition

Mohr

Brühne

Fecht

2016

Physica Status Solidi (a)

View full text Add to dashboard Cite

Nanocrystalline diamond films were grown by hot filament chemical vapor deposition. The thermal conductivity of the films was measured using the 3v-method. Nanocrystalline diamond films grown under the presented growth conditions are rather homogeneous in film properties within the entire film thickness and deposited area. The considerably smaller thermal conductivities, compared to single crystal diamond can be explained by an influence of the grain boundaries with varying grain sizes. We use a theoretical approach to describe the thermal conductivity of nanocrystalline materials to characterize the grain boundaries thermal boundary conductivity also with respect to the growth conditions.

show abstract

Stacking-fault structure explains unusual elasticity of nanocrystalline diamonds

Cited by 18 publications

References 19 publications

Young's modulus, fracture strength, and Poisson's ratio of nanocrystalline diamond films

Young's modulus, fracture strength, and Poisson's ratio of nanocrystalline diamond films

The mechanical properties of various chemical vapor deposition diamond structures compared to the ideal single crystal

Thermal conductivity of nanocrystalline diamond films grown by hot filament chemical vapor deposition

Contact Info

Product

Resources

About