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Also the number of ferrite grains which direction 〈101〉 are parallel with transversal direction of rolling (notification 〈101〉 ║ TD) showed a well observable increment.
A strong correlation between the hydrogen permeability and number of ferrite grains in which normal direction of rolling is the normal of {111} plane is observed at the beginning of cold rolling.
As the fragmentation of the carbides increased, the number of randomly oriented ferrite grains Fig. 6.
When each coarse carbide were fragmented, increasing deformation level again increased the number of ferrite grains in which normal direction of rolling is the normal of {111} plane, as well as the hydrogen permeation time.
Conclusion In cases when no other significant changing in the microstructure can be observed, which can act as major trapping site for the hydrogen, increasing number of ferrite grains in which normal direction of rolling is the normal of {111} plane increases the hydrogen permeation time.

The two-dimensional porosity and grain size were measured using an image design drawing software, based on the number of pixels in the image.
Due to non-uniform grain size and irregular shape, the way in measuring the neck diameter contact and the contact angle are by measuring the all the grain seen on the photograph.
This driving force, that could led a grain growth in the grain boundaries direction would result a pores shrink with an increase of sintering temperature.
While at the end of the sintering process there is no neck growth found, but there is a density increase and coordination number increase [13, 14].
The ceramic produced has a high porosity number and could be a material candidate to be applied in the development of ceramic metal composite.

Segregation thermodynamics indicated that the segregation of magnesium to grain boundaries prevented element such as Cr, C from enriching on grain boundary, which was helpful for the reduction of network carbide precipitation.
Sample numbers was shown in Tab. 2.
But a small amount of uncontinuous network carbide precipitated in the grain boundary.
Part of magnesium segregated to grain boundaries in the thermal processing and may reduce the enrichment of other elements in grain boundary.
Grain boundaries in metals[M].

It was found that pattern quality improves with increasing atomic number with the FIB milling parameters needed to be adjusted accordingly.
The technique was used to investigate the recrystallization behaviour of a particle-containing nickel sample, which revealed a number of features of the recrystallizing grains that are not clearly evident in 2-D EBSD micrographs.
For aluminium, there are also a lower number of clearly identifiable bands compared with both Cu and Au.
The ion-milled surface reveals both silica particles and recrystallizing grains (arrowed).
The first micrograph does not clearly indicate that a particle is associated with this grain but further sectioning reveals a ~ 3 µm particle completely contained within the grain; this is strong evidence of PSN.

The first part is star propellant grain, the second part is tubular propellant grain, and both ends of these parts have a stress reliever.
The total number of C3D10 elements is 61353, C3D8R elements is 364189 as showed in Fig. 3.
Mach number contours of fluid T=1ms T=4ms Fig. 6 b.
The Mach number of the fluid at different step times was studied.
The stress and strain of propellant grain were analyzed.

The ferrite grains have irregular grain boundaries and often show etching evidence of dislocated substructure.
Boundary distribution and equivalent grain size The complexity of the fine-scale microstructure of low carbon bainite is further exemplified with detailed determinations of the numbers and nature of the boundaries in the microstructure.
The larger is the number of boundaries the smaller is the effective grain size.
The number and nature of boundaries in the microstructure obtained by EBSD mapping provides a means of distinguishing between different forms of bainite as well as determining the effective grain size.
<15° 60° Misorientation Angle Lower Bainite Granular Bainite Upper Bainite Number Fraction Fig. 13 Definition of bainite based on distribution of misorientation angles between grains/laths.

For quick references, the sample without bismuth ions was denoted and the samples with increasing concentrations were numbered from “1”, “7”.
The microstructure parameters are ASTM grain size (G) and porosity (P).
The undoped sample (“0”) have a relatively uniform microstructure with relative uniform grains and the density is 4.68 gcm-3; at low Bi2O3 contents (<0.03 wt %) the structure becomes fine-grained and more uniform and the density greater than 4.80 gcm-3; an abnormal grain growth is observed for sample with 0.07 wt % Bi2O3 which density was 4.74 gcm-3; beyond this doping level the samples show a well crystallized microstructure with large grain size, and the 4.83 gcm-3 density.
Fig. 4 Loss factor as a function of ASTM Grain Size and Porosity.
At 0.5 wt% doping level, the segregation of Bi2O3 on the grain boundary and intergranular pores hinder grains growth so the average size decreases.

Second, grain-refinement treatment can be adopted as a method to average stress loaded on each grain and grain boundaries, performing as obstacles to the dislocation’s expansion and movement.
The grain size in Fig.
According to nucleation model proposed by Rappaz and Oldfield, Gaussian Nucleation isdescribed in equation (1), in which n(△T) is nucleation number, △T is actual cooling degree in K; (1) Nucleation density under certain cooling temperature could be confirmed by equation (2), where nmax is max nucleation number; △T in equation (2) is the cooling degree as max nucleation
The small deviation angles for grain growth indicate a good columnar grain structure along the axis direction.
Shape factor is a measure of grains uniformity.

The copper tubes annealed at 780℃ have finer grains and slightly poorer grain uniformity.
The average grain size is 11.45 μm if a twin crystal is considered as a grain.
The average grain size is 22.35 μm if a twin crystal is considered as a grain.
(a) 780℃ grain boundary (b) 810℃ grain boundary (c) 780℃ intragranular image (d) 810℃ intragranular image Fig. 4.
It is known that the 810℃ annealed tube contains a large number of low stacking fault energy twin boundaries, which belong to Σ3 grain boundaries.

When the forging pass is 6, the final forging temperature has an important influence on the grain size in the fine grain zone.
However, high forging temperature is harmful for obtaining ultra-fine grains as grains grow quickly at high temperature.
The number and detail parameters of the samples are shown in Table 1.
Many small grains are distributed on the grain boundary junction (as signed by the arrows).
New recrystal grains are preferentially formed near the grain boundary junctions due to their high energy.