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Most of these works have been focused on grain refining in an attempt to produce ultra fine-grained bulk metals [1].
Thus, FD1=FD2 (the subscripts denote the number of the DCAP pass).
(Feeding roll) (Guide roll) Route A Route B Fig. 2 Schematic diagram of the CCSS process Journal Title and Volume Number (to be inserted by the publisher) D A B C F G H E J K I L L A : 0.5 B : 0.8 D : 1.2 C : 1.0 E : 0.8 F : 1.2 G : 1.6 H : 2.0 L : 1.8 K : 1.7 J : 1.4 I : 1.2 (a) 1 pass (b) Route A (c) Route B Fig. 3 Effective strain distribution for 1pass, Route A and Route B, respectively gap (region “A”).
After even number of DCAP passes, the original shape of the sample is restored.
To enhance the uniform shear strain distribution during DCAP process, it is considered that a sharp die corner is necessary as well as the sample rotation by 180º around the RD after an odd number of DCAP passes.

Test material was 20 ×20× 3mm polycrystalline Si sheet, polycrystalline silicon was composed of a number of silicon atoms and the number of small grains that formed into a silicon crystal.
Due to the arrangement direction ,each grain was different from each other, wherein a large number of defects existed.
The reason of this result was that: the water jet to bring the loss to laser beam energy , while also having the role of the slag erosion, in this experiment, the faster water velocity, the greater the pressure, the jet punch effects had become more significant; after the water punched jet hole wall, so that the surface is smooth on both sides of the hole wall, the laser beam was to increase the number of reflections in the process, then improved the efficiency of the laser.

The microstructure is characterized by dendritic grains with carbides located in interdendritic areas.
The average dendritic grain size was 0.66 mm.
Hysteresis loops for selected numbers of cycles were recorded in disk memory.
Fig. 3 shows the stress amplitude σa as a function of the number of cycles N obtained for both coated and uncoated specimens cycled at 900 °C.
The plastic strain amplitude εap at half-life vs. the number of cycles to fracture Nf is shown in Fig. 6 both for the uncoated and coated material.

We have demonstrated that the layer stacking and layer number strongly influence the stability of graphene film.
This position shows the lowest defect band intensity, which indicates that the stability of graphene increases with the increase of the layer number.
These maps also clearly demonstrate that the layer stacking and layer number have strongly influenced the stability of graphene film.
We found that the layer stacking and layer number have strong influence on the stability of graphene film.
Stafford, Preferential self-healing at grain boundaries in plasma-treated graphene, Nat.

It can be seen that there are some obvious coarse precipitates at the grain boundaries and in the matrix of the samples after isothermal holding at 350˚C for 10 s as shown in Fig. 2 (b), and both of the density and the size of the coarse precipitates in it increase remarkably comparing with Fig. 2 (a).
Fig. 1 Influence of isothermal treatment on conductivity of isothermal quenched samples with 2 mm thickness Fig. 2 Morphologies of precipitates in matrix and at grain boundaries after isothermal quenching: (a) 300˚C for 10 s, (b) 350˚C for 10 s Fitting the TTP curves by the conductivity of isothermal quenched 7050 alloy The increase of conductivity of alloy after isothermal treatment is caused by the decomposition and precipitation of supersaturated solid solution.
(1) Where C(T) is the critical time required to precipitate a constant amount of solute (s); k1 is the constant equal to the natural logarithm of the fraction untransformed during quenching; k2 is the constant related to the reciprocal of the number of nucleation sites (s); k3 is the constant related to the energy required to form a nucleus (J·mol-1); k4 is the constant related to the solvus temperature (K); k5 is the constant related to the activation energy for diffusion (J·mol-1); R is the mole gas constant (J·mol-1·K-1); T is the thermodynamic temperature (K).
It can be seen that the matrix and grain boundaries of the alloy are without any precipitates after two-stage solution and directly water quenched treatment.
It can be clearly observed at grain boundaries and in the matrix of the alloy have appeared a small amount of inhomogeneous precipitated phases with size of approximately 50 nm, which indicates that isothermal holding at 330˚C the incubation period of inhomogeneous precipitation is less than 2 s, corresponding with the calculation results of TTP curves fitted by isothermal quenched conductivity.

For the anisotropy simulations, the two sheet textures were then discretised into sets of about 1000 individual orientations with equal weights, such that the polycrystal is represented by a set of distinct orientations or 'grains' that reproduce the initial texture of the material.
The microstructure of this sheet was comprised of fairly fine grained equiaxed recrystallised grains with an average size of ~25 µm.
Accordingly, the sheet showed a deformed microstructure with elongated grains (Fig. 3).
The Taylor factor Mi of a distinct grain i is defined as the sum of slip contributions Σγj on the j active slip systems necessary to fulfil deformation under the external shape change D, divided by the applied strain ∆ε [1,2].
The experimental yield locus was constructed from a number of different mechanical tests performed at Corus R&D.

It also approved that having nano-sized grains made the effect of passivation more effective rather than the galvanic corrosion [19].
Optical images after polarization tests Conclusions The mechanical properties, corrosion resistance, hardness and microstructural of six different variants of new developed OPH steels were investigated within a number of different tests.
Bublikova, "Influence of thermomechanical treatment on the grain-growth behaviour of new Fe-Al based alloys with fine Al2O3 precipitates," Materiali in Tehnologije, vol. 51, pp. 759-768, 2017
Fratzl, "A thermodynamic approach to grain growth and coarsening," Philosophical Magazine, vol. 83, pp. 1075-1093, 2003
Svoboda, "Using thermomechanical treatments to improve the grain growth of new-generation ODS alloys", Materiali in tehnologije, vol. 52, pp. 475-482, 2018

Second, the small diffraction angles associated with high x-ray energies, when coupled with large two-dimensional detectors, yields diffraction information from multiple grain orientations and hkl-planes in a single exposure, thus enabling kinetic studies of strain evolution. 2.
Diffraction strain for a given grain orientation η is given by the relative shift in the measured radial position rη, or equivalently d-spacing (dη) from the unstrained value: ( ) 0 0 o o d dd r )rr( − = − =ε η η η (1) where r0 and d0 are the unstrained radial position and d-spacing, respectively, obtained from the measurements of the alumina tab.
When heating above ~700ºC these alloy lines disappeared, and the rings became very spotty with diffuse streaks, as expected from the large-grained alloy substrate.
(a) Diffraction image at 1160ºC, showing fine-grained α-Al2O3 Debye cones and spots, with diffuse streaks, from large-grained alloy substrate, with the position of the (116) reflection indicated.
Use of the APS was supported by the U.S Department of Energy, Office of Science, Office of Basic Energy Science, under contract number W-31-109-Eng38.

SEM micrograph (Fig. 3) of the last mentioned sample provides even higher values of the mean grain size, of about 90 nm, implying that powder has agglomerates consisted of two or more single crystallites.
It is possible that the grains growth during the aging process in air atmosphere before XRD measurements is enhanced for this initially much more disordered structure, obtained at the higher current density.
The higher value of the activation energy in the second, high-temperature stage of reaction is probably due to activation of the fine particles - grain growth and sintering processes in both iron and iron oxide (magnetite) powders.
Conclusions The iron oxide powders of various grain sizes were obtained using the electrochemical method, by simple changing the two parameters of the synthesis: current density and temperature of the water solution in the electrochemical cell.
Further examinations will include the influence of the level of non-stoichiometry and incorporation of the elements with small atomic number (Al, Ga, etc.) on the reactivity and kinetics of the considered reduction/oxidation processes in the nanometric magnetite powders.

Uses the domestically produced light ceramsite filler, which grain size is 3~5 mm, porosity of filter bed is 0.312, the thickness of filter bed is 1500 mm.
There installed graded gravel layer under the filter bed which height is 250 mm, grain sizes is 5~8 mm.
In addition, the hydraulic loading increases, making the concentration of organic increase in the upper part of the filter column, increase in the number of aerobic microorganisms, and the corresponding nitrification inhibition (living space is compressed), will lead to a decline in NH3-N removal.
At the same time increase the hydraulic loading to reduce the backwashing cycle, relatively increase the number of washing, which is slow-growing nitrifying bacteria is detrimental to the proliferation, affecting the removal of NH3-N.
In addition, slow the proliferation of nitrifying bacteria, NH3-N concentration in the lower cases, the slow proliferation, the numbers are less.