Development and measurement of single layer thickness standard

2013 ◽  
Author(s):  
Jianjun Cui ◽  
Sitian Gao ◽  
Hua Du ◽  
Xiaoping Zhu ◽  
Liping Yan
Keyword(s):  
Layer Thickness ◽  
Single Layer ◽  
Thickness Standard

Making Graphene-type Material via Polymerization of Porphyrin

2020 ◽  
Author(s):  
SANJIB KAR ◽  
Sruti Mondal ◽  
Kasturi Sahu ◽  
Dilruba Hasina ◽  
Tapobrata Som ◽  
...  
Keyword(s):  
Layer Thickness ◽  
Polymeric Material ◽  
Single Layer ◽  
Type Material ◽  
Synthetic Pathway ◽  
Simple Chemical ◽  
Doped Graphene ◽  
Ring Nitrogen ◽  
2D Structure ◽  
Porphyrin Macrocycles

<p>The synthesis of new graphene-type materials (<i>via</i> polymerization of porphyrin macrocycles) through a simple chemical synthetic pathway (at RT) has been demonstrated. This newly synthesized material can be dispersed in water with an average sheet size of few microns and with single layer thickness. As the porphyrin contains four inner ring nitrogen atoms thus the presented polymeric material will be close analogous of N-doped graphene. Porphyrin as the key component to synthesize layered graphene type continuous 2D structure has never been attempted before. </p> <p> </p>

The sp2 character of new two-dimensional AsB with tunable electronic properties predicted by theoretical studies

2019 ◽  
Vol 21 (37) ◽  
pp. 20981-20987
Author(s):  
Jie Zhang ◽  
Huijun Liu ◽  
Yun Gao ◽  
Xiaohong Xia ◽  
Zhongbing Huang
Keyword(s):  
Electronic Material ◽  
Electronic Properties ◽  
Layer Thickness ◽  
Single Layer ◽  
Theoretical Studies ◽  
Two Dimensional ◽  
Direct Bandgap ◽  
Stacking Order ◽  
Orbital Hybridization

We identify a semiconducting 2D electronic material, single-layer AsB, which has a suitable direct bandgap of 1.18 eV. Its frontiers state is sp2 orbital hybridization, which can be effectively tuned by layer thickness, stacking order and strain.

The Studies on Gas-Bearing Characteristics of Deep Coal Seams in Yanchang Oil and Gas Province, China

2014 ◽  
Vol 962-965 ◽  
pp. 213-216
Author(s):  
Guo Ping Jiang
Keyword(s):  
Coal Seam ◽  
Layer Thickness ◽  
Oil And Gas ◽  
Single Layer ◽  
Gas Content ◽  
Coal Bed ◽  
Coal Seams ◽  
Resource Potential ◽  
Gas Bearing ◽  
Average Layer Thickness

In this paper, four general directions are described to make evaluations and their resource potential; those are coal structure and coal level, gas content of deep coalbed, the coalbed thickness and distribution and the buried depth of coalbed. Coalfields of the study area are mainly Permian and Carboniferous coal seam of Shanxi Formation coal and Benxi group 11 # coal, coal seam depth 1370-1812m. No. 3 coal-seam average layer thickness of 1.6 m, the monolayer most 2 m thick; No. 11 coal-seam in the average layer thickness of 3 m, single-layer thickness of 4.5 m. Predict the amount of coal resources of 17.3 one hundred million t. Predict coal-bed methane resources of 27.68 billion cubic reserve abundance of 104 million square / km2 in. The exploration results show that this region has good development prospects.

Structural and Mechanical Properties of Multilayer TiN/CrN Coatings

2007 ◽  
Author(s):  
Manohar S. Konchady ◽  
Sergey Yarmolenko ◽  
Devdas M. Pai ◽  
Jag Sankar
Keyword(s):  
Mechanical Properties ◽  
Layer Thickness ◽  
Single Layer ◽  
Preferred Orientation ◽  
X Ray Diffraction ◽  
Unbalanced Magnetron Sputtering ◽  
Deposition Parameters ◽  
Unbalanced Magnetron ◽  
Crn Coatings ◽  
Modulation Wavelength

Multilayer and superlattice coatings of TiN/CrN coating are deposited on Si(100) substrate at different modulation wavelength by reactive unbalanced magnetron sputtering and characterized using X-ray diffraction, nanoindentation, AFM. Nano-roughness of films is in good correlation with hardness and modulus and this effect has been used for optimization of deposition parameters. Preliminary results have shown slightly better mechanical properties for multilayered TiN/CrN coatings compared to single layer TiN and CrN coatings. The XRD results have shown a preferred orientation in &lt;100&gt; direction for TiN/CrN multilayer coatings at modulation wavelengths below 80 nm. At 100 nm layer thickness, TiN revealed small amount of crystals with &lt;111&gt; orientation and their content significantly increases with increase in layer thickness while CrN layers only show preferred orientation of &lt;100&gt;. Multilayered coatings exhibit better mechanical properties due to presence of large number of interfaces which act as barrier to dislocations. Fracture toughness and tribological properties of these coatings are also expected to show significant improvement and the investigation in this area is under progress.

Influence of Single Layer-Thickness on Residual Thermal Stresses in Sm2Zr2O7/YSZ Thermal Barrier Coatings

2013 ◽  
Vol 537 ◽  
pp. 97-100
Author(s):  
Ren Xi Hu ◽  
Xiao Ge Chen ◽  
Gang Li
Keyword(s):  
Shear Stress ◽  
Residual Stresses ◽  
Layer Thickness ◽  
Radial Stress ◽  
Thermal Stresses ◽  
Axial Stress ◽  
Single Layer ◽  
Thermal Barrier ◽  
Barrier Coatings ◽  
Barrier Coating

In this paper, influence of single-layer thickness on residual stresses in Sm2Zr2O7/YSZ thermal barrier coating was analyzed by finite element method. Results show that the radial stress remains stable in x range 0-12mm, and it decreases abruptly at edge of the sample. The distribution of axial stress resembles that of radial stress, the shear stress increase abruptly at edge of sample. In three typical residual stresses, radial stress has the highest value, axial stress and shear stress can be ignored. The best thickness combination of Sm2Zr2O7/YSZ TBCs should be 0.1mm-NiCoCrAlY layer, 0.05-0.1mm -TGO, 0.1mm-YSZ and 0.9mm-Sm2Zr2O7

Effects of the Processing Parameters on the Forming Quality of Stainless Steel Parts by Selective Laser Melting

2011 ◽  
Vol 189-193 ◽  
pp. 3668-3671 ◽  
Author(s):  
Qing Song Wei ◽  
Xiao Zhao ◽  
Li Wang ◽  
Rui Di Li ◽  
Jie Liu ◽  
...  
Keyword(s):  
Layer Thickness ◽  
Selective Laser Melting ◽  
Molten Pool ◽  
Laser Power ◽  
Single Layer ◽  
Scanning Speed ◽  
Processing Parameters ◽  
Powder Layer ◽  
Laser Melting

Selective Laser Melting (SLM) can produce high-performance metal parts with complex structures. However, it’s difficult to control the processing parameters, because many factors involves. From the perspective of the molten pool, the study focuses on the effects of processing parameters, including scanning speed, laser power, scanning space, layer thickness, and scanning strategies, on the surface quality, the balling effect, the density of SLM parts, by conducting experiments of single track, single layer and block forming. The results show that the quality of the molten pool is affected by laser power and scanning speed. Scanning drove in the strategy of “jumping and turning”，a smooth surface and a less balling effect will be obtained. The thicker the powder layer is, the lower density will be obtained. The optimal parameters from series of experiments are: laser power of 98W; scanning speed of 90mm/s; scanning space of 0.07mm; layer thickness of 0.1mm; and scanning strategy of “jumping and turning”.

scholarly journals Effect of infra‐red power level on the sintering behaviour in the high speed sintering process

2008 ◽  
Vol 14 (3) ◽  
pp. 155-160 ◽  
Author(s):  
C.E. Majewski ◽  
D. Oduye ◽  
H.R. Thomas ◽  
N. Hopkinson
Keyword(s):  
Optical Microscopy ◽  
Layer Thickness ◽  
High Speed ◽  
Power Level ◽  
Single Layer ◽  
Content Type ◽  
Red Power ◽  
Infra Red ◽  
Sintering Characteristics ◽  
Sintering Behaviour

PurposeTo investigate the effects of the infra‐red power level on sintering behaviour in the high speed sintering (HSS) process.Design/methodology/approachSingle‐layer parts were produced using the HSS process, in order to determine the effect of the infra‐red power level on the maximum achievable layer thickness, and the degree of sintering. The parts were examined using both optical microscopy and contact methods.FindingsIt was initially expected that an increase in the infra‐red lamp powder might allow an increase in the depth of sintering that could be achieved, as a result of increased thermal transfer through the powder. However, results in fact indicated that there is a maximum layer thickness that can be achieved, as a result of part shrinkage in the z direction. Optical microscopy images have shown that a greater degree of sintering occurs at higher power levels, which would be expected to correspond to an improvement in the mechanical properties of the parts produced. These images also indicate that the radiation absorbing material forms in small “islands” on the powder bed surface. As sintering progresses, these islands begin to merge; this occurs to a greater extent at higher infra‐red lamp powers.Research limitations/implicationsThese results are based only on single layer parts. Further work will examine the sintering characteristics of multiple layer parts.Practical implicationsResults have shown that, whilst it is not possible to increase the achievable layer thickness of the parts produced by modifying the infra‐red lamp power, the degree of sintering can be improved greatly by increasing the power.Originality/valueHSS is an entirely new process which is currently still under development; the results presented here will directly impact the direction of further development and research into this process.

Thermally Driven Shape Instability of Multilayer Structures

1999 ◽  
Vol 581 ◽  
Author(s):  
P. Troche ◽  
J. Hoffmann ◽  
C. Herweg ◽  
CH. Lang ◽  
H.C. Freyhardt ◽  
...  
Keyword(s):  
Layer Thickness ◽  
Single Layer ◽  
Local Variation ◽  
Interfacial Stress ◽  
Multilayer Systems ◽  
Thermally Induced ◽  
Transmission Electron ◽  
Thermally Driven ◽  
Interface Curvature ◽  
Means Of Transmission

ABSTRACTThe thermally induced shape instability of Fe/Au, Fe/Ag, and Nb/Cu multilayer systems during heat treatments was investigated. The disintegration temperature of these systems decreases with decreasing single-layer thickness. Up to a critical thickness, the disintegration temperature is proportional to the reciprocal layer thickness. The driving force of this process is related to the interfacial stress and the local variation of the interface curvature. After heat treatment, spherically shaped Fe and Nb nanoparticles, located in chains perpendicular to the substrate, were observed and depicted by means of transmission electron microscopy (TEM) and X-ray microscopy (XRM).

Sign in / Sign up

Export Citation Format

Share Document