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ITTO film deposited at room temperature showed the enhancement in (400) orientation and the increasing in grain size.
With an increase in annealing temperature, the intensity of XRD peak increased and the grain size showed an evident increasing.
Fig. 2 Variations of I(222)/I(400) ratio and lattice parameter (a), grain size and FWHM (b) of annealed ITO and ITTO films.
Annealing can promote crystalline growth, which contributes to the activation of the dopant and reduces the number of donor sites trapped at the dislocations and grain boundaries and increases the carrier concentration.
The grain boundary scattering decreases with the increase in annealing temperature and the growth of grain size.

It is found that the addition of Nb and Ti can effectively refine the dendrites of the steel to equiaxed grains.
In addition, the phosphorous in the steel is moved from the grain boundaries into the multi-carbides. 1.
Nb also can restrain the P segregation at the grain boundaries [6].
Both of these two elements can form the net-like shape carbides that locate on the grain boundaries.
The solubility of Ti and Mo in the NbC is greater than that in the matrix or other phases, so Ti and Mo also accumulate in the NbC, and the atomic number of Mo is similar to Nb, it is possible for Mo to replace the Nb in the carbide.

The disc samples were deformed by a HPT apparatus under an applied hydrostatic pressure of 5 GPa for a number of rotations (N) up to 100.
Meanwhile, the right half of the area is composed of equiaxed grains with about 50 nm.
Increasing the degree of deformation caused an increase in the number of twins on the primary {111} plane as well as other {111} planes intersecting the primary twins.
There have been a number of reports on twinning in the g’ phase after creep deformation at temperatures above 1000 K [22].
The observed high strength should originate from grain size strengthening and solid solution hardening since it is fully disordered in the nano-grains to form a super-saturated solid-solution of Ni-25mol%Al.

The measured resistivity is influenced by a number of microstructural factors such as the precipitate size and the volume fraction, the vacancy concentration, the concentration of solute in the matrix etc. [6].
Grain size analysis was conducted by the line intercept method.
Grain size corresponding to each heat-treatment case was obtained as an average from multiple specimens.
A LEO 1530 scanning electron microscope was used for examining sub-grain microstructural features.
The average grain size post-vacancy stabilization at 1045°C increased by not more than 15% of the as-solution-treated grain sizes.

The misorientation threshold between high and low angle grain boundaries was chosen to be 15°.
The microstructure of the as hot rolled samples is characterised by equiaxed grains with an average grain diameter of 195 µm (cf.
Grain growth stage.
Larger grains are developed in non-heavily deformed samples [11], as it is shown in Fig 4b.
Further deformation introduced such an extraordinary number of defects that the Kikuchi band contrast of the patterns dropped significantly.

The hardening effect is achieved through drastic grain refinement down to ultrafine-grained range as well as pronounced substructure strengthening.
This technique promotes the formation a fine-grained or even ultrafine-grained structure in the welded material and thus normally results in excellent mechanical properties of welds.
Typical microstructure of base material: (a) EBSD grain-boundary maps and (b) TEM image.
As expected, FSW led to drastic grain refinement.
Acknowledgements This work is supported by the Ministry of Education and Science of the Russian Federation under the agreement №14.584.21.0023 (ID number RFMEFI58417X0023).

For a given route and pass number, the texture developed with Φ = 120° is generally weaker than its counterpart with Φ = 90°.
Introduction Equal channel angular extrusion (ECAE) has been successfully applied to produce ultrafine-grained materials in various materials through severe plastic deformation (SPD) [1,2].
It is also not yet confirmed that the optimal processing route for grain refinement is always among the three basic routes.
It had equiaxed grains with an average grain size of about 60 μm (see Fig. 1).
The textures are the weakest with route R180 for both die angles, regardless of the pass number.

The solid ice and snow constitutive model was established, which the deformation mechanism of snow microstructure and macroscopic continuous behavior were linked together, considering the damage of solid ice and snow depends on the mechanical properties of the snow volume elements of the grain bonds between grains, and using the microstructure factor scale the stress state of microstructure in the continuous stress.
The constitutive model The microscopic model of ice and snow The mechanical behavior depends on the snow volume elements of the grain bonds in grains was taken into account when established the model.
Namely, considering the macroscopic behavior was controlled by the movement of skeleton of ice grains.
Fig.1 Microstructure definitions Fig.2.Continuous description of the normal direction of contact Definition of representative volume element A volume element around a point was considered when analyzed the model, in which the number of grain bonds is large enough so that this volume can be described as a continuous material.
Definition (a) and modelling (b) of an ice bond between two grains in contact Microscopic contact stress analysis The contact form of ice grains as shown in Fig.3, when analyzed the mechanical properties of ice grain bonds, taken the gravity effects into account, a stress state is generated at each point of the neck.

Scherrer method was used to determine the grain size [23] based on the (101) reflection.
It can be observed that as the grain size coarsens the lattice volume of anatase changes for heat treatment times of less than 8 h that correspond to a grain size of less than ~17 nm and changes in band gap are also observed at similar times.
During coalescence and coarsening of anatase some of the “disordered” atoms, usually at the grain boundary, combine with the atoms of neighbouring grains.
This in turn resulted in the formation of larger crystallographic planes and number of T and O atoms forming molecules that is reflected in the XRD and BET results.
For example, the grain size determination (by Scherer) is clearly demonstrated with the TEM dark field micrographs.

Although the synthesis of high purity alumina powders has been successfully achieved in a large number of publications, the consolidations of powders to full or nearly full density without appreciable grain growth are still a practical challenge[7].
The samples with an average grain size around 500 nm were obtained, which had a relative small grain growth compared with the precursor powders adopted.
In the TSS method, the sintering proceeds at low temperatures, which may keep the grain-boundary diffusion active but suppress the grain-boundary migration, for the grain-boundary migration has a higher activation energy than the grain-boundary diffusion [42].
A full-dense structure with the grain size of ~500 nm was achieved, a remarkable decrease in grain size were achieved compared with that of samples produced by conventional sintering[45].
It was proved that under very low vacuum pressure, oxygen partial pressure could deplete the diffusion from the contracting grain to the expanded grain[47].