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Recrystallised grains in the turbine blades designed to be used in single crystal form are one example.
Where plastic strain is accumulated and it exceeds a critical limit, recrystallised grains occur.
The situation corresponding to a cylindrical, constrained bar have been modelled using ProCAST, with care being taken to ensure that the mesh is sufficiently fine for the results to be independent of element number.
Byrne: Recovery, Recrystallisation and grain growth.
Mould: Recrystallisation and grain growth in metals.

This depicted enhanced mechanical properties of coatings comprising nano-grains of about 10 nm.
Furthermore, by using Scherrer’s equation, this film could be seen to be composed of CrAlN grains with average size of 20 nm.
However, if the N is inadequate, the metallic atoms form the AlCr alloy phase surrounding the Cr1–xAlxN grains.
This thickness increment results from the higher number of Al sputtered atoms from the increasing sputter current.
Xie, Designing superhard, self-toughening CrAlN coatings through grain boundary engineering, Acta Mater. 60 (2012) 5735-5744

The total elongation was increasing as the annealing time increased from 4 h to 12 h, which could be attributed to a large number of retained austenite formation.
This could be due to the fact that the microstructure of the pre-quenched steel was patial martensite with a large number of dislocation and lattice distortion, which provided a fast passage for the diffusion of C and Mn elements [9].
As shown in Fig. 5(a), the retained austenite in steel with traditional direct two-phase annealing was mainly blocky morphology embedding in polygonal annealed martensite grain boundaries.
The microstructure of the steel after direct two-phase annealing process consists of coarse tempered martensite matrix and blocky retained austenite embedding in martensite grain boundaries.
This can be due to the fact that the microstructure of the pre-quenched steel is partial martensite with a large number of dislocation and lattice distortion, which provids a fast passage for the diffusion of C and Mn elements.

The developed method of cast iron inoculation allows to eliminate the flare and to increase the physical and mechanical properties of the castings through the grain refining and the decrease of chilling tendency during crystallization of the liquid alloy.
There are some methods of obtaining nanodiamonds, shock-wave synthesis [1], which has a number of undeniable advantages over the probabilistic method, is the most efficient and fastest in time.
Grain size of the binder metal, [µm] 210…230 20…30 Results To reveal the structure of the metal base, the samples were etched with 4% nital.
As can be seen from the above, the developed method of refining and inoculating allows to eliminate the flare and to increase the physical and mechanical properties of the castings through the grain refining and the decrease of chilling tendency during crystallization of the liquid alloy.
Grain size in the structure of mold castings, [µm] 160…170 30…50 2.

Then the paper analyzed phase composition and crystal structure of samples using XRD and calculated the average grain size of samples by Scherrer formula, and observed and analyzed by TEM to characterize the morphology and particle size of samples.
But if the reaction time is too short, crystal structure is unstable and intermediate products obtained as a jelly which are difficultly filtered and format hard bulk solids as it had dried and be difficult to re-open, and in the middle of that would be mixed with a large number of inorganic salts solution.
In Figure 4, the width of diffraction peaks is clear, indicating the sample prepared in the optimum conditions is small grain.
According to CuO (111) crystal plane corresponding to the width at half maximum, using Scherrer formula D = Kλ / βcosθ calculations , the average grain size of the sample prepared in the optimum conditions is 18nm.
This process is simple, low cost, easy to implement the characteristics of industrial production; (2) by researching the main factors, affecting the nano-CuO yield in the reaction, the results showed that the optimum conditions are: precipitation dosage 3.2:1, reaction time of 40min, the concentration of precipitant of 0.6mol.L -1, and then the copper yield is 96%; (3) through the results, which were obtained by XRD and Scherrer formula, the average grain size of samples, which were synthesized in optimum conditions is 18nm; through analyzed by TEM, these results and the results of Scherrer formula is consistent.

As the service temperature of the turbine discs increases, the grain structure develops from fine grain to coarse grain, and then to dual microstructure.
The dual microstructure which consists of fine grain bore and coarse grain rim has a high potential for optimal performance.
Special care was taken to ensure that the resulting pillars were completely embedded in individual grains to avoid grain boundary effects [12].
A certain number of annealing twins were formed during recrystallization process due to the hot working as shown in Fig. 3b.
Fig. 3 Grain structure of the alloy samples (a) SEM micrograph of grain structure.

Al-4%CNTs was refined into finer grains when AgNPs are present.
The Al-4%CNTs+2%Ag.NPs composite produces a higher dislocation density because of the production of sub-grain.
Fig.5a. presents abundant evidence of large grain boundaries in the α-Al structure.
These whitish phases can increase the number of free electrons and augment both conductivity and energy storage of Al.
Mor inclusion of AgNPs to Al-4%CNTs generally resulted in further grain refining of the Al-4%CNTs.

We concluded that the fisheye areas and the number of quenching steps were strongly correlated.
By end of life, we mean the number of cycles at which the bar specimen breaks due to a fisheye crack.
At high number of cycles (Nf), the fisheye aspect ratio showed a tendency to decrease.
Fisheye facet occurred at non-heat treatment affected zone as large ferrite grain.
Fisheye cracks towards the specimen surface were halted by small grains in the heat treated area.

Acoustic, mechanics and physical properties of seabed sediment samples is measured by professional equipments and parameters such as porosity, density, grain average size, P-wave velocity, attenuation and other data can be obtained.
For a digital image with gray value range [0, L-1], its discrete function of histogram is given by: (5) Where k is the gray value of , is the number of gray value equal k in the image.
As k and d have been obtained, so the sediment mean grain size can be calculated from Eq.(10).
Seabed sediment can be classified by use of the mean grain size.
Whereas, the frequency of sub-bottom profile system is relatively low, it can penetrate a certain depth seafloor strata and the echo signals contains a large number of geological attribute information, acoustic characteristic parameters such as porosity, permeability can be inversed through rational model, and then sediment mean grain size can be calculated.

Gibbs Free Energy at the Magnetic Domain Family Scale In the following, g denotes a grain.
Simplifications can concern the loading itself and some homogeneity hypotheses that can be applied: - homogeneous stress at the grain scale: σα=σϕ=σg - homogeneous temperature over the volume: Tα=Tϕ=Tg=T - homogeneous magnetic field at the grain scale: Hα=Hϕ=Hg Only stress and magnetic field have usually to be localized (to be defined as function of loading at the upper scale).
The total number of internal variables strongly depends on the number of phases (n), variants (m) and number of domain families (p) inside each variant.
Some localization rules are required to define the stress and magnetic fields at the grain scale (they are supposed homogeneous over the variants and magnetic domains) [8].
The localization procedures from the RVE to the grain scale makes it possible to better account for demagnetizing fields and residual stresses effects [13].