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Grain refinement as one of the strengthening methods can lead to good strength and ductility.
Cryorolling can produce not only ultra fine grain material but also continuous and long material.
The results mean that the cryorolling can increase the number of the dislocation loops.
Therefore, an appreciable number of vacancies can be kept after solution treatment.
(4)Cryorolling can increase the number of the dislocation loops when the alloy solution treated and aged at 170˚C for short time.

The grain is considered as an uniform region neglecting the formation of the dislocation microstructure.
The grain undergoes a strain eII (with a stress sII) composed of an elastic part ee and a plastic part ep.
The elastic strain rate is linked to the stress rate in the grain through the Hooke’s law: (5) where s is the elastic compliance tensor at the grain level.
is the accumulated slip in the cell in the grain I .
This number of crystallites has been chosen to simulate the polycrystalline aggregate in an efficient way.

Totally, 54 experimental tests were implemented with different Froude numbers and concentration ranges.
In order to mix the fine-grained sediments used in this experiment and to prevent their settling, three agitators, one at the upstream and two in the downstream were designed and fixed in the model.
The sediments used in this research include washed fine-grained sand with d50=0.173mm and a wet density of 1.99 (t/m3), the gradation curve of which is shown in Figure 2.
Nevertheless, the changes are not tangible in small Froude numbers; the larger the flow Froude number, the smaller the submerged depth on the gate.
They are more sensible at Froude number 4.5 and so, and at numbers larger than 5, about 6% decrease is observed.

Reduction in both the nonlinearity index and the amount of δ-Bi2O3 for small amounts of added Bi with the addition of more than approximately 1.25 mol% Sb2O3 demonstrates that Sb inhibits Bi2O3 from forming deep interfacial impurity levels at the grain boundaries.
Some commercial ZnO varistors contain Sb, which increases the varistor voltage by reducing the grain size of ZnO.
The addition of Y to a Bi-based ZnO varistor with added Sb reduces the average grain size of ZnO and enables the varistor voltage to be doubled; however, resistance to electrical degradation is also reduced and the leakage current is increased [4,5].
The reduction with the addition of Y to Bi–Mn–Co–Sb–Si–Cr–Ni-added ZnO varistors (with the same composition as a commercial varistor) is caused by an increase in the number of willemite (Zn2SiO4) particles or by a reduction in the number of spinel Zn2.33Sb0.67O4 particles at the grain boundary between two ZnO grains.
The thin Bi2O3 layer at the grain boundaries is necessary to form the potential barrier caused by deep interfacial impurity levels improving the nonlinear V–I characteristic.

Mechanical properties of the weld joint can be improved [4] by introducing high-melting particles to the molten metal which increases the number of induced crystallization centers reducing the grain size during hardening [1, 2].
Nanocrystalline particles of high-melting tungsten were introduced to increase the number of induced crystallization centers.
The structure contains polyhedrous grains with traces of twin formation.
The average size of the grains was 30±10 micrometers.
The sample also features short highly branched dendrites which are located in the grains.

In deep bed wetting simulation analysis, deep bed grains are usually regarded as comprising a number of thin layers, calculated step by step, to get the final result.
Figure 1 is the influence of hot air temperature, humidifying rate and grain consumption of grain temperature on unit heat Simulated conditions of figure 1 is: grain types for brown rice, valley bed thickness of 0.6 m, initial moisture content of grain was 13%, grain flow 800 kg/m2. h, air moisture content is 0.005 kg.kg-1.The grain initial temperature is 20˚C, hot wind speed 0.4 m/s.
Higher grain temperature, grain quality decline, (a) (b) Fig.1 Effect of hot blast temperature on the unit heat consumption, humidification speed and grain temperature from machine of emerging so hot air temperature should not exceed 40 ˚C.
When the air temperature is 20 ˚C, the machine of grain temperature is around 16 ˚C, when air temperature is 25 ˚C, the machine of grain temperature is about 23 ˚C, when air temperature is 35 ˚C, the machine of grain temperature is about 28 ˚C.
Simulated conditions of figure 2 is: the grain types for brown rice, valley bed thickness is0.6m, nitial moisture content of grain is 13%, grain flow 800kg/m2.h, air moisture content is 0.005 kg.kg-1, initial grain temperature is 20 ˚C, air temperature is 25 ˚C.

It is noted here that gadolinia doped ceria oxides are expected to show regions II and III as they have a large number of oxygen vacancies.
It will significantly reduce the numbers of free vacancies available in the crystal lattice.
The grain boundary and grain interior conductivity in microcrystalline Ce0.8Gd0.2O1.9 (CGO 20) versus grain size (0.7 - 17 μm) showed that the grain boundary conductivity increased above 3 μm [120] though conductivity of grain interior remained almost constant.
The grain interior conductivity was independent on grain size.
Tuller, Mixed ionic–electronic conduction in a number of fluorite and pyrochlore compounds, Solid State Ionics. 52 (1992) 135-146

After sufficient number of pulses (typically 15 to 20) of LEHCPEB treatment, this hardened zone can extend over hundreds of µm [9].
The more advanced dissolution process of the carbides [16], together with the ultra fine grain size of the matrix grains [14, 19] are considered to be important factors for the stabilization of the γ phase.
These ultra fine grains are not the only reason for the surface hardening.
This is illustrated by the EBSD map shown in Fig 3b where (i) the sub-grains are visible as white lines and (ii) the grains have blueish colors coresponding to near <111> orientations [29].
The number of pulses of LEHCPEB treatment is also shown to affect the microstructure in different manners.

The structure is represented by large grains elongated in the direction of heat removal.
Introduction The development of additive manufacturing technologies makes it possible to use an increasing number of methods and approaches to obtain products for industrial, aerospace and rocket-space applications.
As a result, in the upper part of the cylindrical part of the sample the orientation of grains is more close to vertical.
The metal structure in the main part of the part is represented by large columnar grains that extend in the direction of heat removal during printing.
A dendritic structure with chromium particles localized between dendrite branches is clearly visible inside the grains.

Hence `pattern number' is equivalent to `minutes into the sintering cycle'.
The numbering is not continuous due to some runs being interrupted.
This means that the average grain size is increasing.
), then during cooling the FWHM increases as the grains shrink in size.
Presumably upon cooling parts of the ferrite grains turn back into austenite leaving smaller grain sizes and broader peaks.