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It is shown that the simulations can correctly reproduce the softening effect linked to a decrease in thickness and in number of grains across the thickness: the quality of the final shape strongly depends on the number of grains across the thickness.
For dimensions larger than a few micrometers, these modifications involved by miniaturization are due to a decrease in the number of grains across the thickness (also called thickness to grain size ratio, t/d ratio).
(a) Barkhausen noise in plastically strained Nickel with two different grain sizes [6].
Optimization of the mechanical properties of this product is typically a size effect because of the very small dimensions of the IMC interlayer and the weak number of grain through thickness for copper external layer.
Geers, An experimental assessment of grain size effects in the uniaxial straining of thin Al sheet with a few grains across the thickness, Mater.

In addition, with more nano-carbides adding, the number of white core grains increases and that of black core grains decreases.
Furthermore, the number of white core grains increaseswith more nano-carbides adding, In cermet D there are many white core hard grains.
Apparently, crazy grain growth occurs in cermet C, or D with nano-micro carbides, where big grains ,up to 5 µm, and small grains less than 0.5 µm coexist, and the heterogeneous microstructure results in poor material performances.
Judging from the forming process of the three hard grains, it is apparent that the microstructure of white core grain is superior to black core grain in improving material performances, wing to much more homogeneous composition transition of different phases .
Furthermore, with the addition level of nano carbides increasing, the number of white core grains increases and that of black core grains decreases.

So is the case as between powder grains.
At the same time, with the increase of the coordination number, the surface curvature of free grains converts from convex to concave.
Coordination numbers in dense structures are found to be at 12.5-14.5 [5].
When this coordination number is achieved, the rearrangement of grains becomes impossible and the initial stage of the sintering process is over.
The relation between packing density and coordination number is shown in Fig. 5.

To facilitate the measurements of strain gradients inside the grains, a specimen with very large grains has been chosen.
The procedure of recrystallization and grain growth was optimized in order to obtain grain sizes of about 5 mm.
Sample with large grains.
A meshed sample with its grains numbered.
Grain 3: a.

The EBSD data of samples showed that normalization can half the grain size after primary recrystallization, raise the percentage content of favored grain boundaries and high-angle grain boundaries, increase the content of Goss orientation grains by 5 times.
Its superior performance attracted a large number of research scholars.
Analysis showed that the grain size in the {111} <11 > orientation and Gaussian grain matched the orientation relationship of high mobility grain boundary.
CSL Grain Boundary Analysis.
Data in Table 4 show two-phase normalization increased the content of ∑9 grain boundary particularly which favored Gaussian grain growth: it also favored growth of the high-energy grain boundary.

Microstructure observation indicates that Yb-α-sialon consists of equiaxial grains, but when increasing the radius of the doped cations, the elongated α-sialon grains form and the aspect ratio of grain increases slightly.
Some elongated α-sialon grains with grain core were found.
Surrounding the grain core, some misfit dislocations were seen.
In order to control the nucleation and obtain elongated α-sialon grains, some α-sialon seeds have been added into starting powers and effects of the size, morphology and number density of seeds have been studied [7].
Yb-α-sialon is entirely composed of equiaxed grains.

A number of studies were carried out in the work, which included testing samples in a heat-treated state and free.
The structure includes a relatively small number of alloying elements.
The greater the indentation depth, the lower the hardness number HR.
The flat surface of the specimen was sequentially polished with various types of emery paper - first coarse-grained (M40), then medium-grained (P800; P1200), then fine-grained (P1500; P2000).
In comparison with the free state of the metal, where the structure is fine-grained, after heat treatment, the structure of the studied steel SS34 becomes homogeneous and an increase in grains is observed.

The growth grains is directly related to diffuse mass transport along grain boundaries from the regions under the compressive stress to condensate at the surface and combines with adjacent grains and forms secondary grain growth[4],[5].
With the grains growing, the mean surface roughness has been increasing significantly.
For DC magnetron sputter deposition, substrate is only as a carrier to receive the sputtered atoms, and the number of sputtered atoms is merely relationship with energy and density of Ar+.
That is the characteristic of the substrate, such as substrate temperature, can not determine the number of sputtered atoms.
The grains are growing and the surface is performing rough with heating the substrate.

In the method, the fine-grained particles are subjected to partial melting and compacting.
Therefore, it is problematic to produce the ingots with fine-grained structure.
Therefore only a limited number of alloys having a wide solidus - liquidus range are used in these technologies.
As a result the granules with fine-grained structure (grain size ≈50 µm) or coarse-grained structure (grain size ≈350 µm) were formed correspondingly (Figure 1).
In the case of fine-grained granules the "reinforcement" possessed fine-grained structure.

The damaged area and the number of deformed grains, which could be identified as dark reflection in optical microscope images was evaluated at certain numbers of loading cycles semi-automatically by using an image analysis software.
Grain size (D), average number of grains per cross section (ζ), ultimate tensile strength and Young's modulus (E).
The small number of deformed grains in the type A copper can be partially attributed to strengthening effect as described by the Hall-Petch effect where due to a higher density of grain boundaries in the films with a smaller grain size, the dislocation movement is hindered.
This effect is mainly due to a larger increase in the number of deformed grains with the type B copper.
This is especially pronounced with the thin 5 µm films where the deformation density with the type B copper is twice as high at 150◦C compared to room temperature while there is only very little increase in the number of deformed grains in the type C copper.