Search results

An appropriate deletion criteria was used to attain minimum energy grain boundary.
Mis-oreintation angle Cell size (Å) Number of atoms W (Å) Crack size (2a) (Å) 1. 44.8° 145x340x121 250148 120 50 3.
In the absence of crack, the grain boundaries are comparatively at higher stress than the crack tip.
Roles of grain boundaries in improving fracture toughness of ultrafine-grained metals.
Blunting of a brittle crack at grain boundaries: An atomistic study in BCC iron.

One can observe that heterogeneity in the mechanical properties generally tends to decrease with the number of ECAP passes.
Dependency of mechanical properties of titanium VT1-0 on the number of ECAP passes Variation of the mechanical properties with the number of ECAP passes (Fig. 2) corresponds to the classical pattern, i.e. with the number of passes, strength properties tend to increase, and plastic properties, to decrease.
For both of the ECAP routes, heterogeneity decreases with the number of passes.
References [1] Beyerlein I.J., Li S., Alexander D.J., Necker C.T., Tome C.N. and Bourke M.A., "Heterogeneity in Texture Development in Single Pass Equal Channel Extrusion", Ultrafine Grained Materials III, ed.
"Sample Size Effect on the Mechanical Behaviors of UFG Ti-6Al-4V Alloy", Ultrafine Grained Materials III, ed.

Regional silk fabrics price index curve, grain sewn damask fabrics price index curve and 14654 grain crepe damask fabrics price index curve are shown in Figure.1.
The establishment of grain sewn damask fabrics price index BP artificial neural network model Take 14654 grain crepe damask fabrics price index for example, the paper uses 100 sets of data as the training sample and10 sets of data as a test sample to analyze.
Using Levenberg-Marquardt method, increase the number of neurons in hidden layer according to trail-and-err, determine the number of neurons in hidden layer when Network error smallest and training fastest [4].
Table.1 The results of different model Hidden neurons Times Iterative-number Hidden neurons Times Iterative-number 1 15 0.00116 15 9 7.81×10-6 2 66 1.33×10-5 16 6 7.34×10-6 3 2000 1.21×10-5 17 32 9.52×10-6 4 49 9.89×10-6 18 5 3.72×10-6 5 63 9.86×10-6 19 38 9.28×10-6 6 70 9.94×10-6 20 43 9.33×10-6 7 53 9.81×10-6 21 7 2.06×10-6 8 24 9.84×10-6 22 24 9.12×10-6 9 44 9.77×10-6 23 27 9.61×10-6 10 25 8.82×10-6 24 5 4.97×10-10 11 7 8.64×10-6 25 36 8.16×10-6 12 19 7.97×10-6 26 5 8.30×10-6 13 6 5.34×10-9 27 10 9.45×10-6 14 18 8.48×10-6 28 9 7.59×10-6 In the same way, set up BP artificial neural network model for second class silk fabrics price index and 14654 grain crepe damask fabrics price index.
Corresponding the number of hidden layer neurons were selected16, 25 and 24.

At lower sintering temperature of 1150°C, the dominant phase was rhombohedral which matches with JCPDS file number 73-2022 while tetragonal phase (JCPDS file number 33-0784) became dominant at higher sintering temperature (1200 - 1250°C).
The grains of all samples had regular shape with clear grain boundaries.
Thus, larger content of the grain boundaries obtained in the sample with smaller grain size can improve hardness value.
This result was partly attributed to the grain size effect.
For ceramics with smaller grain size, smaller number of domains or, in same case, even a single domain can form inside each grain.

It is found that Pr affects the grain size, electrical properties and the dielectric properties of the TiO2-based varistors.
A number of low-voltge varistor materials were reported such as TiO2, SnO2 and SrTiO3 ceramic[4-6].
It can be seen that the grain sizes increase with the increase of dopant concentration, meaning that the dopant can promote growth of grains.
But as a whole, the shape of the grains is almost the same.
Where is the number of grains per unit length and the voltage barrier width.

Initial microstructure contains 100 grains.
This number of the grains correspondents to the average grain size about 80 mm.
The changes of average grain size for entire process can be seen in Fig. 2f.
Depending on temperature, strain and strain rate, the different grain size were obtained.
These parameters influence on the number of new grains and their growth rate.

Sub-micron crystalline silver grain structure were observed using SEM micrographs.
Fig.5(a) shows a uniform small grain with diameter around 100 nm.
The facetted grain shown in Fig.5(b) to 5(f) appear to be nonuniform in grain sizes.
Fig.5(f) shows a higher facetted grain sizes with average grain sizes around 450 nm.
Our results agreed well with others studies [6-9] which report that as the sputtering power increases, the number of energetic atoms and mobility of atoms on substrate surface increases resulting in deposited films became more facetted with larger facetted grain sizes.

The difference of grain size is remarkable, which the farther the grain is away from rivet head top, the smaller grain size is.
However, the grain boundary is relatively clear and a large number of grains produce twins as shown in Fig.4 (a).
The grains within the ASB are severely elongated, then the grains on both sides of ASB crush and distribute along the ASB as shown in Fig.4 (b).
In the small deformation zone, grains crush severely and grain boundaries are not obvious.
Large deformation mainly concentrates on upper side of ASB, while grains deformation on lower side of that is small and most of grain boundaries are clear.

This simulation model can be used to optimize forging process chains with respect to grain size distribution as well as cost effectiveness and energy consumption.
Outside of the deformation zone, only marginal changes occur in the modeled physical values, allowing for a simulation that uses a coarser mesh, and thus, reducing the total number of nodes and elements.
The use of the multi-mesh method for this example has lowered the number of nodes and subsequently, the number of degrees of freedom by 48 % when compared to a mesh with uniform element size distribution.
The time saving is lower than the reduction of the number of the degrees of freedom to be simulated because of the additional data transfer operations and the additional memory required by the multimesh method.
The models describing the kinetics of recrystallization as well as the grain size development due to recrystallization and grain growth, introduced by Sellars et. al [5-7], are applied.

The growth orientation of grains also changed with the number of spin-coating cycles.
With the increase of spin-coating number, the proportion of Se atoms decreases, resulting in a transition to a sulfur-rich state and thereby causing a shift towards an increased diffraction angle [16,17], and also promoting the growth of Sb2S3 grains.
As the number of spin coating increased to three and four, the grains in the film grew, yet the surface morphology deteriorated.
The grain size of the thin film gradually grew.
Acik, Analysis of grain orientation and defects in Sb2Se3 solar cells fabricated by close-spaced sublimation.