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Aydiner et al. determined the grain-resolved stress tensors for several grains in a coarse-grained (100 μm) Mg alloy sample with a cross-sectional diameter of 1.2 mm, that was subjected to plastic deformation [10].
Such samples tend to give rise to overlap of diffraction spots from a large number of grains on the area detector, which is a serious problem with the 3DXRD technique.
To overcome this problem, we previously proposed a scanning 3DXRD technique [14], in which a two-dimensionally focused microbeam is used to reduce the number of diffraction spots in the recorded pattern.
Because only the grain at point Q is always illuminated by the incoming beam, it can be assumed that the ratio of the number N of recorded diffraction spots to the theoretical number M of diffraction spots from a single crystal with the same orientation is larger for this grain than for all other grains.
The scanning 3DXRD method is useful for polycrystalline samples with a large number of grains in a given cross section.

We developed a multilayer system formed by introducing a number of thin silicon oxide layers into the polycrystalline silicon layer.
The number, and the thickness, of the buried silicon oxide layers determine the gettering properties of the multilayer structure.
If the number of buried oxide layers is low then the thickness of the single polycrystalline silicon layers is significantly greater than the lateral grain size.
In order to optimize the thickness and number of the buried oxide layers we prepared a number of structures.
The number of buried oxide layers was varied from 3 to 9.

Introduction In order to improve the mechanical properties such as strength and toughness, a large number of studies have been made on the grain refinement [1-3].
Grain size in recrystallization field was smaller.
The average of the initial grain size was 0.05 mm.
Grain size increased with increasing the time interval.
The grains obtained by the collision of two times were refined and the field of the grain refinement expanded.

Strain rate sensitivity of ultrafine grained fcc- and bcc-type metals J.
In particular, the differences between conventional grain size (CG) and ultrafine grain size (UFG) are pointed out.
The applied strain rate is always indicated by numbers, e.g. "-4" stands for a strain rate of ε& = 1×10 -4 s-1.
In Fig. 3a tensile tests for the recrystallized reference material and after different number of ECAP passes is plotted.
In (a) the curves are labelled by the number of passes and the applied route.

Effect of Aging on Microstructure and Performance after superplastic deformation of fine grained 1420 Al-Li alloy Yanling Zhanga, Hongliang Houb *, Yaoqi Wangc Beijing Aeronautical Manufacturing Technology Research Institute, Beijing, P.R.China a zhangyanling205@163.com, b hou_hl@163.com, c xiaoqigh@sina.com Keywords：Fine grained 1420 Al-Li alloy, Superplastic forming, aging, strengthening mechanism Abstract: Superplastic forming (SPF) is an important process for forming fine grained 1420 Al-Li alloy.
The microstructure of the plates is shown in Fig 1 and the average grain size is about 12μm.
It is found that a large number of cavities are existed in post-SPF materials.
A large number of δ’ phase (Fig.8(a)) which is the major strengthening phase are existed and distributed homogeneously in material after two-step aging.
A large number of δ’ phase are precipitated and distributed homogeneously in material after two-step aging for post-SPF. β（Mg2Al3）and S（Al2MgLi）phases are also exsited, and S phase can improve coplanar slipping which is created by δ’.

The influence of cooling rate on grain size of Mg-Zr alloys was also investigated.
This exceptional grain-refining ability of Zr has led to the development of a number of commercially important sand casting creep-resistant alloys[5].
Their dimension is as big as grain size of near 200μm.
Summary of morphology and dimension of Zr-rich core Zr addition,% Mould Morphology of Zr-rich Diameter of Zr-rich, μm Morphology of grain 1.20% copper round 7.54 fine equiaxed grain steel Round + rosette-like 11.3 fine equiaxed grain Sand 1 round 19.1 equiaxed grain Sand 2 round 29 coarse equiaxed grain 0.70% copper equiaxed grain steel equiaxed grain Sand 1 equiaxed grain Sand 2 rosette-like 200 equiaxed grain 0.30% copper Columnar grain steel Columnar grain Sand 1 Columnar grain Sand 2 Columnar grain The grain sizes for the alloys solidified in four moulds were given in Fig.5.
The grain size increased with decreased cooling rate.

As the data submitted in work fail contain enough observations, it is necessary that a results number allowed to make adjustment with the minimum error.
Summary Using the statistical analysis technique of size grains distribution histograms it is shown that when forming of a grains structure in single-phase metal materials processed by HPT, several groups of grains with different characteristics having various mobility of grains borders can be formed.
Semionkin, Mössbauer Spectroscopy of Grain Boundaries in Ultrafine-Grained Materials Produced by Severe Plastic Deformation, Bull.
Stolbovsky, Emission Mössbauer spectroscopy of grain boundaries in ultrafine-grained W and Mo produced by severe plastic deformation, Phys.
Stolbovsky, Emission Nuclear Gamma-Resonance Spectroscopy of Grain Boundaries in Coarse-Grained and Ultrafine-Grained Polycrystalline Mo, Defect and Diffusion Forum. 364 (2015) 147-156

The grains are the cutting tools during lapping.
In the first one, the grains roll in the working gap.
The number depends on the lap plate size.
It was verified if the plate temperature is influenced by the abrasive powder number.
For experiments three numbers of abrasive powder were taken: F400/17, F800/6.5, F1200/3.

The adsorption process is determined by the concentration of the solute in the fluid next to the solid grain in individual pores.
The adsorption is represented as an equilibrium process where the chemical potential of the solute in the fluid next to the solid grain is equal to the chemical potential of the solute adsorbed to the grain [12].
Therefore, the coarse-grained Peclet number (Pe) can be obtained by the case of a non-adsorbing solute (i.e., k=0) in Fig.2.
As the upscaled Peclet number has been estimated, only two upscaled parameters, ka* and kb*, are left to be determined as a function of pore-scale parameters.
The larger scale kinetic adsorption parameters are obtained as a function of pore scale parameters such as Peclet number and distribution coefficient.

The cavities at the triangle grain boundaries are present in V-shape, others near the second phase particles and within grains are present in O-shape.
The number, shape and distribution of cavitation after superplastic deformation greatly affect mechanical capability of parts.
Cavities on grain boundary join into each other.
But the strengthen phase CuAl2 and Al2CuMg of the original structure in tensile specimen has taken place big change in number, shape and size.
The numbers, sizes of cavity have apparently increased, and the superplasticity also is less than that of Fig.3 (a).