Nanoindentation of ultra-hard cBN films: A molecular dynamics study

Huang, Cheng; Peng, Xianghe; Fu, Tao; Zhao, Yinbo; Feng, Chao; Lin, Zijun; Li, Qibin

doi:10.1016/j.apsusc.2016.09.037

Cited by 34 publications

(9 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…12,13 Theoretically, Li et al 14 found that bond rearrangement at twin boundary can remarkably enhance indentation shear strength in nt c-BN under indentation compression and shear strains. Huang et al 15 applied molecular dynamics simulations for the responses of c-BN lms under nanoindentation, and found that during the indentation, plastic deformation of c-BN is can mainly be attributed to stress-induced slips of dislocations along {111}<110> orientations. In addition, Wang et al 16 reported the synthesis and characterization of transparent bulk diamond/c-BN alloy, and showed that the alloy has a superior chemical inertness over the polycrystalline diamond and a higher hardness than a single crystal.…”

Section: Introductionmentioning

confidence: 99%

Atomic structure, electronic properties and generalized stacking fault energy of diamond/c-BN multilayer

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Introductionmentioning

confidence: 99%

Atomic structure, electronic properties and generalized stacking fault energy of diamond/c-BN multilayer

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…The load-depth ( P-h ) curves are shown in Fig. 2 , where the load is positive rather than zero when h = 0, as in the work by others 46 , 47 , which can be attributed to the repulsion between the indenter and the specimen atoms when their distance becomes smaller than the equilibrium one ( r c = 2.68 Å in Fig. 2 ) if using a “real” indenter rather than using a fictitious one described by a repulsive potential 48 .…”

Section: Resultsmentioning

confidence: 74%

In-plane anisotropy and twin boundary effects in vanadium nitride under nanoindentation

Peng

Huang

et al. 2017

Sci Rep

Self Cite

View full text Add to dashboard Cite

Twin boundaries (TBs) have been observed in and introduced into nonmetallic materials in recent years, which brought new concepts for the design of new structural materials. However, the roles of TB on the mechanical properties and strengthening/softening of transition metal nitrides remain unclear. To investigate the TB effects and the in-plane anisotropy, nanoindentations on VN (111) films with and without TB were simulated with molecular dynamics, in which a cylindrical indenter was used, and its longitudinal axis were assigned along <112> and <110>, respectively. We found that the effect of the indenter orientation is insignificant in the elastic stage, but significant in the following inelastic deformation. Different deformation mechanisms can be found for inelastic deformation, such as twinning and dislocation glide. The migration of TB can be observed, which may release the internal stress, resulting in softening; while the dislocation locking and pileup at TB can enhance the strength. We also found that the strengthening/softening induced by TB depends on the deformation mechanisms induced by indenter directions.

show abstract

“…These estimates can be imprecise when there are a small number of samples, which may account for the poor predictive capability of the LDA for relatively small sample sizes that improves and stabilizes for larger data sets of MD simulations. These results point to a number of possible applications of this method, for example in quantifying how the range of damage for a set of strained systems may depend on strain rate or temperature, or quantifying similarities between complex damage from processes such as indentation [13,[34][35][36][37] and the interaction of energetic ions with solids [38][39][40][41][42] in terms of materials and damage conditions.…”

Section: VImentioning

confidence: 95%

Statistical and image analysis for characterizing simulated atomic-scale damage in crystals

Reich

Brenner

2017

Computational Materials Science

View full text Add to dashboard Cite

While molecular dynamics simulations have been used for decades to study structure and formation mechanisms of plastic damage in crystals, the analytical tools needed to characterize collections of plastic defects have been limited. Here we demonstrate the use of two methods, spatial cross-correlations (CC) and Linear Discriminate Analysis (LDA), to analyze and compare plastic damage profiles among molecular dynamics simulations in which damage was created by straining bi-crystals containing symmetric tilt grain boundaries with different tilt angles. Two potentials were used, one representing Cu and one representing Ag, and two coarse-grained descriptors for different types of crystal damage were used, averaged central symmetry parameters (CSP) and atomic hydrostatic stress (HS). We find that in general the CSP is a more accurate descriptor than HS for both analysis methods, and for data base sizes of about 30 or more simulations per tilt angle, the LDA does considerably better in predicting angle and material than the CC method. For example, at the largest data base size of 50 simulations per tilt angle and using the average CSP values, the LDA predicts the exact initial tilt angle and material type for 92% of the simulations, while the CC approach drops to 58%. If the average HS is used instead of the average CSP, the LDA and CC predictions drop to 63% and 32%, respectively. These results point to a number of possible applications of this method, for example in quantifying how the range of damage for a set of strained systems may depend on strain rate or temperature, or quantifying similarities between complex damage from processes such as indentation and energetic ion bombardment.

show abstract

Nanoindentation of ultra-hard cBN films: A molecular dynamics study

Cited by 34 publications

References 46 publications

Atomic structure, electronic properties and generalized stacking fault energy of diamond/c-BN multilayer

Atomic structure, electronic properties and generalized stacking fault energy of diamond/c-BN multilayer

In-plane anisotropy and twin boundary effects in vanadium nitride under nanoindentation

Statistical and image analysis for characterizing simulated atomic-scale damage in crystals

Contact Info

Product

Resources

About