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After refinement and outlier rejection the final number of reflections per grain was ~90.
The number of grains that can be mapped simultaneously is limited by the extent of peak overlap, which is more severe for textured and/or deformed materials.
Between 248 and 329 grains were indexed and refined in each layer, and after refinement and outlier rejections the final number of reflections per grain was ~55.
The reason for this can be found in the number of assigned reflections per grain, which is 90 for IF steel because the grains were allowed to compete for multiple assigned reflection, compared to 55 for Cu where all multiple assigned reflections were rejected.
The approach has proven to be superior in performance with respect the number of grains that can be mapped and the accuracy to which the grain resolved properties can be determined.

The P-Mg2Si grains can be further refined by addition of very small percentage of grain refiner element.
Some α-Al grains appear also in the bulk of the melt.
Globularization of Mg2Si grains in Sr added Al-15Mg2Si-4.5Si composite collected after the slope exit and undergone through isothermal holding stage, is taken into account in the phase field simulation by reducing the number of facets corresponding to the Mg2Si phase.
The fragmentation of Mg2Si grains is taken into account in the phase field simulation by invoking higher number of nuclei, which is done by adjusting the shield time and shield distance, which signify the time span during which no nucleation event will occur after generation of one nucleus up to the shield distance around the nuclei [18].
A single Mg2Si grain is formed from the coalescence of multiple grains.

There are limited number of studies were dealt with examination of the Hall-Petch relationship in Al-Mg alloys.
Distinct areas of fully recrystallized grains with an average size of ~1 mm alternate with unrecrystallized grains (Fig.3b).
The formation of low number of deformation-induced LABs takes place in this strain interval.
Experimental datum points were fitted to straight line with a high accuracy (Fig.6) despite a great difference in dislocation density and density of LABs between deformation structures produced by different number of passes.
Lee, W.J.Nam, Microstructures developed by compressive deformation of coarse grained and ultrafine grained 5083 Al alloys at 77 K and 298 K, Mater.Sci.Eng.

Formation of fairly large grains (crystallographic domains) of graphene exhibiting sharp 1x1 patterns in m-LEED was revealed and that different grains showed different azimuthal orientations.
A grain size of up to a few mm was obtained on some samples.
appear in the LEEM image the reflectivity curves show that most have the same number of graphene layers.
They were collected at two different locations outside the area shown in Fig. 1a) but where the number of graphene layers was also six.
ordered grains.

(3) where the parameters are: ψ=exp(η/2), ψ = exp(-η/2), ϕ≈bV/Deff, with C, the macroscopic atomic concentration of Mn; N, number of atoms per m3 (1/b 3); E0, interaction energy in the grain boundary; k, Boltzmann factor; η= kTE /0 ; b, interatomic distance in the lattice; V, velocity of the grain boundary and Deff the effective diffusion rate.
The analysed grains during the experiments were those with "random" grain boundaries.
The "tilt" grain boundaries or the grain boundaries, which showed impingement, were excluded from the present study.
Because the rapid recrystallization grains were too fast to be followed and because grain impingement occurred in the very early stage of the annealing experiments only the slower recrystallization grains were tracked.
Grain boundary mobilities and activation energy The grain boundary mobility (M) of each HAGB of the recrystallizing grains was obtained by dividing the grain boundary migration rate (V) by the current driving force (P) for temperatures of 200-300°C.

The nano-sized grains of ~300 nm were obtained after 8 ECAPs at 373 K and 473 K.
Introduction A number of research studies have been recently attempted to obtain the nano-structure in metallic materials by imposing severe plastic deformation (SPD) such as equal channel angular pressing (ECAP), accumulative roll bonding (ARB) and high torsion pressing (HTP), etc [1].
The starting materials showed the average grain size of approximately 200 �.
Near equiaxed nano-sized grains of ~300 nm was introduced by 8 ECAPs at 373 K and 473 K, although the grain size at 373 K was slightly smaller than that at 473 K.
However, in case of pressing at 473 K, the improvement Journal Title and Volume Number (to be inserted by the publisher) in strength was found without sacrificing much of elongation.

The results show that composite lead-free solder after constant 125˚C aging treatment for 24 hours, Al particles has two types of morphologies: one is small amount of solid solution，another type is a large number of aluminum particles structure.The existence of Al particles slowed down the coarsening rate of the Bi Phase grain, and obtained uniform refined the Bi Phase grain.
In figure 3, the black particles are Al particles which have both small amount of solid solution and a large number of aluminum particles structure exist at the Sn-58Bi solder.
Because the Al powder prevent the Bi phase grains from growing up and getting together.
It is composed by β-Sn grains and sheet Bi grains.
With 3.0N stress aging treatment, grains in the brazing joint still keep small.

The continuity requirements of strain components across the grain boundary plane between grain 1 and 2 is given by the following relationship [1]: (1) (2) yy yyε ε= , (1) (2) zz zzε ε= , (1) (2) yz yzε ε= , ( 11 ) here, (1) yyε for example, denotes the sum of elastic and plastic strain components and the number in superscript denotes the grain.
The continuity requirements of strain components across the other grain boundary planes, which are lying parallel to z-x plane, are represented by the following relationship: ( ) ( ) n m xx xxε ε= , ( ) ( ) n m zz zzε ε= , ( ) ( ) n m zx zxε ε= , ( 12 ) Fig. 1 Geometry and boundary condition for the models employed in this study here, n and m denote number of neighboring crystal grains.
The combination of crystal orientations for grains 1, 2 and 3 are chosen so that the angle(α) between loading direction and slip direction of the primally slip system are (1) α = (2) α =44° and (3) α =46°, here, the number in superscript denotes the crystal grain number.
Table 1 Grain number, Euler angles�κ,θ,φ�, Value of components of slip direction vector ( )9th b and slip plane normal vector ( )9th v of primary slip systems Grain Num.
�κ�θ�φ�[deg] (9 )th xb (9 )th yb (9 )th zb ( )9th xv ( )9th yv ()9th zv 1 (74.983, 24.535, 79.469) -0.6947 0.7193 0 0.7193 0.6947 0 2 (74.983, 24.535,259.469) 0.6947 0.7193 0 -0.7193 0.6947 0 3, 5 (79.645, 24.973, 75.236) -0.7193 0.6947 0 0.6947 0.7193 0 4, 6 (79.645, 24.973,255.236) 0.7193 0.6947 0 -0.6947 0.7193 0 Table 2 Grain number and values of Schmid tensor (9 )th ijP Grain Num

There are undissolved second phase particles in grains and at grain boundaries.
Second phase particles can be found in grains and at grain boundaries.
The second phase particles appeared at grain boundaries and in grains.
There were some fine dispersion η' precipitates, about a few nanometers size, needle-like shape, and a small number of spherical GP zone precipitation in grain.
After aging treatment, alloy microstructure separated out a large number of dispersed strengthening phases, so the hardness must be improved.

HIPIB irradiation experiment is carried out at a specific ion current density of 1.1 J/cm2 with shot number from one to ten in order to explore the effect of shot number on electrochemical corrosion behavior of magnesium alloy.
The improved corrosion resistance is mainly attributed to the grain refinement and surface purification induced by HIPIB irradiation.
With increasing shot number, numbers of crater reduced, but size of crater increased owing to the repetitive melting and evaporation/ablation under HIPIB irradiation.
Fig. 4 shows the potentiodynamic polarization curves of the original and irradiated samples with shot number from one to ten.
More importantly, grain refinement took place on the outer surface of irradiated sample, which have been identified by TEM observation.