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Application to Welding: In order to model solidification of the weld pool using a granular approach, a number of modifications are required to the components outlined above.
A few columnar grains are also shown in (c) to highlight the difference between two major kinds of grains.
Welding microstructure produced using the improved algorithm: (a) equiaxed grains in the base metal; (b) columnar grains; (c) equiaxed grains at the weld center; (d) assembled image.
It is also assumed that the grain sizes for the equiaxed grains near the base metal, the columnar grains and the equiaxed grains at the center of this weld are 50, 200, and 30 µm.
As each grain contains on average 60 elements, and the simulation consists of 3800 grains, there will be a large number of liquid channels to evaluate.

Fig. 1 XRD pattern of TiC-TiB2 composite prepared in the experiment FESEM images and EDS results showed that a large number of randomly-orientated, fine TiB2 platelets were uniformly embedded in the irregular TiC grains, and Cr metallic phases located between TiC crystals and TiB2 crystals, moreover, a few of α-Al2O3 inclusions were also observed, as shown by the isolated black particles in Fig. 2, and some largeα-Al2O3 inclusions measured about 5 μm in diameter at surface area of the samples were observed in Fig. 3 especially.
Owing to the face-centered cubic structure, a lot of slip system exist in TiC crystal in room temperature, so the crack develop easily when the crack contact the TiC grain [5].
The compressive stress will release near the crack tip as soon as the crack contact the TiB2 grain.
However, when the crack meets the coarsened TiC grains and Al2O3 inclusions, transgranular fracture is presented, as shown by the arrow C and arrow D in Fig. 8.
XRD, FESEM results showed that the TiC-TiB2 ceramic was mainly composed of a large number of fine TiB2 platelets, irregular TiC grains, a few Cr-Al metallic phases and a few of isolated irregular α-Al2O3 inclusions.

Finishing polishing was performed on Al2O3 paste with grain size 0,25µm.
The results of the size measurements of the QE22 grain Parameter symbol unit QE22 - unmod.
QE22 - mod. acc. to MEL QE22 - mod. +50% QE22 - mod. +100% grain size area of flat section A [µm2] 9229 2484 774 543 number of grain per unit area NA [mm-2] 106 395 1274 1808 relative area of grain boundary SV [µm2/µm3] 0.026 0.048 0.084 0.105 heterogeneity of the grain size variation coefficient A ν(A) [%] 102 83 81 77 grain shape shape factor ξ - 0.635 0.662 0.662 0. 644 elongation factor δ - 1.64 1.67 1.78 1.65 Table 5.
The results of the size measurements of the RZ5 grain Parameter symbol unit RZ5 - unmod.
RZ5 - mod. acc. to MEL RZ5 - mod. +50% RZ5 - mod. +100% grain size area of flat section A [µm2] 7207 871 589 534 number of grain per unit area NA [mm-2] 135 1132 1669 1837 relative area of grain boundary SV [µm2/µm3] 0.029 0.084 0.103 0.110 heterogeneity of the grain size variation coefficient A ν(A) [%] 91 72 73 70 grain shape shape factor ξ - 0.627 0. 582 0. 617 0. 605 elongation factor δ - 1.59 1.69 1.63 1.62 a) b) Fig. 3. a) the results of the mid area plane section measurements of the grain, as well as the volume fraction of the eutectics with the variant of modification for QE22 alloy, b) the results of the average area of plane section measurements of the grain, as well as the volume fraction of the eutectics with the variant of modification for RZ5 alloy.

In contrast, in the samples with high ductility, larger NbC precipitates with lower number densities are observed.
BN precipitates develop number densities of approx. 1012 m-3.
Also, the relatively small number density of 1014 particles per m3 gives a number of 10-4 particles per µm3, which strongly decreases the chance of detecting any such precipitates in TEM.
Finally, AlN tends to precipitate on austenite grain boundaries.
Grant Agreement number: RFSR-CT-2011-00008.

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.

Austenitic grain pattern is observed with Olympus GX71 optical microscope.
Figure 5 shows that the original grain in the deformed structure is obviously stretched at the strain rate of 10s-1, grain boundary suffers serious fragmentation, and a small amount of dynamic recrystallization grains appear near the triple junction and grain boundary, the grain size being smaller, and the amount of cores decreasing.
Compared with the deformed structures at strain rate of 10s-1 as shown in Figure 5, the dynamic recrystallization area of the deformed structures at strain rate of 1s-1 expands, and the original grain is gradually replaced by dynamic recrystallization grain with the size of newly generated grain enlarging and the number of cores decreasing.
The dynamic recrystallization behavior occurs more fully in the deformation organization, and the grain boundaries of the stretched original grains become basically obscure, larger grains of dynamic recrystallization being formed in the boundary zone, and being distributed in a homogeneous manner as shown in Figure 6.
Meanwhile the dynamic recrystallization is not complete under higher strain rate with newly generated grains mainly concentrated in the area close to the grain boundary of the stretched original grains, the proportion of which being low and the distribution of which being uneven.

Key words: organosilicon modified styrene-acrylic emulsion; reflectivity; grain size; film thickness.
balance. 1.3 Formula design In order to reduce the number of test, L9(34) orthogonal table was selected for orthogonal test,and the interplay between each factor was left out ,shown in table 1.
Fig.5 Size distribution chart of rutile titanium dioxide 2 Grain size range of rutile titanium dioxide 2 is from 0.082µm to 0.088µm,coating made with this sample has reflectivity of 66.70%.
Pigment grain size has main effect on the coating reflectivity as soon as the pigment selected.
(3) Grain size analysis showed that pigment has maximum reflectivity when grain size range is 0.107µm~0.687µm

After rolling, Al8Cu4Er phase could be fragmentated into dispersed particle which leaded to an increase of the grain boundary strengthening .
Some coarse bright particles were present in grain-boundary eutectic structure.
After hot rolling , Al8Cu4Er particles were crushed up along with the grain boundary (Fig.5b) .
The precipitation of Ω phase also includes the nucleation and coarsening .The number of nucleation site and coarsening force affect the distribution and the size of Ω precipitate .
As discussed above , addition of Er in alloy decreased the number of Ag/Mg co-clusters.

For the simulation of martensite plates, 2 austenite grains are grown on a grid with 80 martensite nuclei placed on the boundaries of the austenite grains.
The computational cost is only dependent on the size of the domain and not the number of grains of martensite, bainite or austenite.
Each grain is assigned a global ID in order to distinguish it from other grains.
The treatment involving global IDs enables the simulation of two or more grains in close proximity without the model being confused as to the identity of each grain.
Yang, Computer simulation of the domain dynamics of a quenched system with a large number of nonconserved order parameters: The grain-growth kinetics, Physical Review B 50(1994)

The maximum number of passes by routes A, Bc, and C was N = 25, which corresponds to a true deformation ε ~ 29.
The distributions of the grain sizes and the grain boundary misorientations were determined using Orientation Imaging Microscopy (OIM).
Results and discussion The strength characteristics upon ECAP reach a constant level at a number of passes N = 5 and then do not change until N = 25 (Fig.1a).
The samples deformed by route Bc to N = 15 and N = 25 exhibit a small number of relatively coarser grains, of 1-1.5 µm in size.
Kuznetsov, in: Ultrafine Grained Materials IV, edited by Y.T.