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The grain size effect was not noticeable because the selected grain sizes were much larger than that of the micro feature.
There are a number of surface patterning methods that can chemically and physically modify surfaces but many of them do not have high production efficiency and economy characteristics.
Considered factors Forming steps [number of steps] Forming velocity [µm/s] Grain size [µm] Friction coefficient Values 1, 2 0.5, 1.0, 1.5 25, 60, 100 0.05, 0.10, 0.20 Results and Discussions The example results of the microimprinting simulations are shown in Fig. 3.
In Fig. 4(b), the variation of grain sizes barely affected the peak errors because the feature size of the micro pattern was much smaller than those of the grain sizes.
Selected grain sizes did not affect the peak errors.

However, extensive grain growth occurs under subsequent solution treatment resulting in coarse grained structure.
It is seen that coarse unrecrystallized grains retain their elongated shape; normal growth of recrystallized grain leads to the formation of grains having equiaxed shape with size ranging from 4 to 20 μm.
In contrast, discontinuous grain growth in the samples processed by ECAP up to strain of ~8 and ~12 leads to the formation of bimodal coarse grained structure (Fig.3b); size of largest grains exceed average size of grains in as-cast condition.
It is worth noting that increasing strain from ~2 to ~8 leads to transition from elongated grains to grains with equiaxed shape which resulted from discontinuous grain growth.
It seen that there is a minor effect of numbers of ECAP passes on strength and plasticity.

Nomenclature A Total cross-sectional area of the beam b Breadth of beam bpl Breadth of plank deck ca per Applied compressive stress perpendicular to grain cb par Basic compressive stress parallel to grain cg per Grade compressive stress perpendicular to grain cm per Mean failure compressive stress perpendicular to grain COVcper Coefficient of variaton for compressive stress perpendicular to grain COVfpar Coefficient of variation for bending stress parallel to grain COVvpar Coefficient of variation for shear stress parallel to grain COVUw Coefficient of variation for unit weight of the Nigerian grown Iroko cp per Permissible compressive stress perpendicular to grain E Modulus of elasticity for the Nigerian grown Iroko Emean Statistical mean value of modulus of elasticity Emin Minimum value of modulus of elasticity EN Statistical minimum value of E appropriate to the number of pieces N acting together F Form factor dependent on the cross-sectional shape of the
Forty test specimens of the Nigerian grown Iroko timber were prepared for each of the following tests; bending strength parallel to the grain, tensile strength parallel to the grain, compressive strength parallel to the grain, compressive strength perpendicular to the grain and shear strength parallel to the grain.
Figures 1 – 4 show the Nigerian timber test samples for compression parallel to the grain, bending parallel to the grain, tension parallel to the grain and shear parallel to the grain respectively.
(6) where EN is the statistical minimum value of E appropriate to the number of pieces N acting together (where N=1, EN becomes the value for Emin) and σ is the standard deviation.
From Ozelton and Baird [10] (30) where EN, is the statistical minimum value of the modulus of elasticity for the number of pieces acting together, Emean is the mean value of modulus of elasticity and N is the number of pieces acting together at a cross-section.

For example: orientations, dislocation densities, grain sizes etc.
The grain structure corresponds to material points within the box marked O.
These nuclei are then allowed to grow and erase the old grain boundaries.
(b) Proportion of new CA cells to the total number of cells in a finite element.
Fig. 4b shows the proportion of new CA cells that are occupied by the recrystallised nuclei to the total number of CA cells associated with an integration point.

The homogeneity of grain size was also improved.
Therefore, a number of scholars have reported various of methods to overcome these shortages and then improve the properties of magnesium alloy.
With FUT treatment, another morphology (acicular β phase) replaces the laminar β phase, and the number of small β phase increases at the same time.
With VUF treatment, the β phase become smaller than FUT treated billet, showing the increased number of dot-like phases.
The homogeneity of grain size was also improved.

These nodules are composed of finer grains less than 5nm as shown in Fig. 2c.
This can be explained in terms of its finer grain size with higher active.
The only different is the number of nanoparticles and their sizes.
In this study, P25 coating presents "cauliflower" structure with about 5nm in grain size which increases significantly the number of active sites and contact areas with benzene.
The only different is the number of nanoparticles and their sizes.

A number of the larger grains of the α-phase were also observed in the structure, which partially or completely lost its nearly lamellar structure.
All the EBSD maps were taken from a small number of grains of parent β-phase (Fig. 1c - two grains of the parent β-phase with similar orientations).
The number and type of Ci -matrices depends only by the type of lattice of the phase in which the transformation develops.
Acknowledgement This study was financially supported by the State Assignment, grant number 0836-2020-0020.
Winning, Five-parameter grain boundary analysis by 3D EBSD of an ultra fine grained CuZr alloy processed by equal channel angular pressing, Adv.

The formation mechanism and evolution of liquid pools entrapped within solid grains have been investigated during partial remelting of in-situ Mg2Si/AM60B composite with fine-grains during partial remelting.
Many investigators have studied the microstructural evolution during partial remelting and found that large numbers of small liquid pools is formed within primary particles [9,10].
The added Sr and SiCp aimed to modify Mg2Si phase and refine primary α-Mg grains.
These inclusions (marked by D in Fig. 2(a)) distributed within the grain.
A large number of smaller liquid pools were appeared (marked by E in Fig. 2(b)), and these liquid pools formed from the residual eutectic phases within the grain or the decomposed eutectic β phases.

The two-dimensional porosity and grain size were measured using an image design drawing software, based on the number of pixels in the image.
Due to non-uniform grain size and irregular shape, the way in measuring the neck diameter contact and the contact angle are by measuring the all the grain seen on the photograph.
This driving force, that could led a grain growth in the grain boundaries direction would result a pores shrink with an increase of sintering temperature.
While at the end of the sintering process there is no neck growth found, but there is a density increase and coordination number increase [13, 14].
The ceramic produced has a high porosity number and could be a material candidate to be applied in the development of ceramic metal composite.

It appears impossible for a sufficient number of abrasive grains to exist in the machining area.
As a result, abrasive grains are concentrated and fixed around the tool tip [7].
Therefore, such a concentric pattern indicates that the tool tip is pressed against the workpiece and a sufficient number of abrasive grains could not be concentrated around the tool tip.
In addition, such chain shapes appear to prevent abrasive grains from being supplied to the machining area.
With these locations, it is believed that the chain shapes of ER particles and abrasive grains would not prevent abrasive grains from being supplied, and the machining of high-aspect ratio micro holes appears to have been achieved.