A Molecular Dyanamics Study of the Nano-indentation on Polyethylene Single Crystalline : The Effect of Chain Orientation

Nano-indentation test is used widely to determine the fracture toughness of brittle materials and to provide information on important material properties such as the Young’s modulus and hardness. In this study, using nano-indentation testing, atomic force microscope (AFM), and finite element method (FEM), we performed the indentation fracture toughness and fracture strength measurement for a (100) single crystalline silicon at different load states. In addition, the loads of the phase transformation events during unloading were estimated by the load-depth curves. The phase transformation load and micro-crack propagation events at pop-out during the unloading process depended on the maximum applied indentation load.

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Measuring Microscopic Properties of a Single-Crystalline Diamond by Nano-Indentation Technology

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1120-1121.378 ◽

2015 ◽

Vol 1120-1121 ◽

pp. 378-382 ◽

Cited By ~ 1

Author(s):

Qi Long Wei ◽

Xiao Bin Yue ◽

Xiao Yuan Li ◽

Bo Liu ◽

Xiao Feng Zhang ◽

...

Keyword(s):

Great Influence ◽

Fused Silica ◽

Diamond Surface ◽

Measurement Properties ◽

Indentation Hardness ◽

Silica Sample ◽

Single Crystalline ◽

Nano Indentation ◽

Indentation Force ◽

Before And After

Nano-indentation technology was brought to study microscopic mechanical properties of a single-crystalline diamond (SCD). Nano-indentation measurement was conducted on the {100} plane of SCD, and influences of various factors on measured results were analyzed, from which methods were confirmed to improve veracity of measurement. Properties of the indenter were checked with a fused silica sample both before and after indentation on diamond, which provided guarantee to veracity of results on diamond. It was found that tilt of diamond surface had so great influence that it could damage the indenter, and make the indentation curves anomalous. While damage of indenter could be avoided and valid measurement results could be obtained when tilt of diamondsurface was decreased below 0.10º and the maximal indentation force was less than 10 mN. Deformation of the diamond was almost full-elastic during indentation process. Indentation hardness of {100} plane of the SCD was about 70 GPa with standard deviation less than 3 GPa. And there had good reproducibility between two groups of measurements.

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Fracture Characteristic of Single Crystalline Silicon Using Nano-Indentation and Finite Element Analysis

Fracture and Strength of Solids VI - Key Engineering Materials ◽

10.4028/0-87849-989-x.601 ◽

2006 ◽

pp. 601-606

Author(s):

Seung Baek ◽

Jae Mean Koo ◽

Chang Sung Seok

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Crystalline Silicon ◽

Fracture Characteristic ◽

Single Crystalline Silicon ◽

Element Analysis ◽

Single Crystalline ◽

Nano Indentation

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“Preparation of Single Crystalline Gold Films for ED Studies”

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096424 ◽

1972 ◽

Vol 30 ◽

pp. 634-635

Author(s):

Joseph D. C. Peng

Keyword(s):

Crystal Morphology ◽

Diffraction Theory ◽

Scattering Matrix ◽

Vacuum Evaporation ◽

Gold Films ◽

Matrix Formulation ◽

Silver Films ◽

Single Crystalline ◽

Grating Pattern ◽

Stacking Disorder

The relative intensities of the ED spots in a cross-grating pattern can be calculated using N-beam electron diffraction theory. The scattering matrix formulation of N-beam ED theory has been previously applied to imperfect microcrystals of gold containing stacking disorder (coherent twinning) in the (111) crystal plane. In the present experiment an effort has been made to grow single-crystalline, defect-free (111) gold films of a uniform and accurately know thickness using vacuum evaporation techniques. These represent stringent conditions to be met experimentally; however, if a meaningful comparison is to be made between theory and experiment, these factors must be carefully controlled. It is well-known that crystal morphology, perfection, and orientation each have pronounced effects on relative intensities in single crystals.The double evaporation method first suggested by Pashley was employed with some modifications. Oriented silver films of a thickness of about 1500Å were first grown by vacuum evaporation on freshly cleaved mica, with the substrate temperature at 285° C during evaporation with the deposition rate at 500-800Å/sec.

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