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After MDF, the grain size is refined down to below 11 microns with a starting grain size of 13 microns.
The grains are relatively coarse and irregular in shape.
The grain boundaries are more distinct and well-defined.
The grain size after MDF is dictated by the mutual effects of dynamic recrystallization and grain refinement in the microstructure.
Previous studies have shown that the MDF method can be used to fabricate alloys with extremely fine grains by increasing the number of forging cycles and annealing processes [17,18].

Self-assembly of symmetric diblock copolymers (DCP) confined in multiwalled carbon nanotubes (MWCNTs) is studied using coarse-grained molecular dynamic (MD) simulations.
In this paper, coarse-grained MD method is adopted to simulate the interaction energy and self-assembled structures of DCP within MWCNTs.
Model and Methods The computer simulations in our study are based on coarse-grained MD method.
The chain length of the polymer is N =8, and the number of the A and B monomers in a chain are NA = NB = 4, respectively.
Conclusions We have performed coarse-grained MD simulations to study the self-assembly of symmetrical DCP confined in MWCNTs.

Such microstructural variation leads to the formation of smaller Co grains (with respect to the as deposited sample) closely distributed around each Ag grain surface.
We have used such geometry [7,8] in order to reduce the number of micrometric particulates (Ag metallic molten droplets, in our case) that usually cause poor surface quality of laser ablated films.
They should be formed by smaller grains, whose scanning, however, is limited by the tip size and by the presence of the 50 nm diameter grains come across the scanner travel.
The average Ag grain size can be estimated to increase from about 25 nm in the as deposited sample to 50 nm in the LB sample, while further annealing induces a more marked grain growth as it can be also inferred from the usual grain growth behavior.
After irradiation, Ag grains size increases up to 50 nm.

To achieve thin sheets, TRC sheets are hot rolled in a number of passes and intermediate annealing depending on the thickness reduction and target gauge.
Therefore, the relative frequencies of fine grain size (<5 µm) and coarse grain size (>10 µm) where accumulated and compared (Fig. 2).
Due to low thickness reduction per rolling pass, the number of dislocations und therefore nuclei for dynamic recrystallization (DRX) is reduced.
This leads to a lesser quantity of recrystallized grains per volume, hence increased grain size, whereas sheet thicknesses of 0.6 mm to 1.0 mm contain more than 50 % of fine grain in their microstructure.
Smaller grains increase the possibility of favourably orientated grains and GBS [28].

Macroscopic behavior of materials is a function of microscopic phenomena, e.g. dislocation interactions, grain interactions, and grain divisions.
These element groups are numbered from 1 to 10 as the crystallites of the polycrystal and are assigned initial crystallographic orientations which are identical to the ones in the reference [1].
Fig 5 shows rotations of grain 1, grain 7, grain 8, and grain 10 after ~ 15 % thickness reduction.
Rotation of (a) grain 1.
(b) grain 7 (c) grain 8, and (d) grain 10 Conclusion We use our dislocation density based CPFEM model for studying microstructure evolution in a 2D columnar polycrystal.

SEM photographs show that the nanocrystalline diamond films consist of unfaceted diamond grains.
Further investigation using AFM reveal that the average size of the grains is 50-100 nm.
Journal Title and Volume Number (to be inserted by the publisher) 89 Raman scattering is 50-60 times higher for sp 2-bonded carbon compared to sp 3-bonded carbon, hence the diamond component dominates in films.
We can see two sets of lattice fringes distinctly inside the grain.
These films appear very smooth, homogeneous, with a fine-grained morphology.

Rice Husk or Rice Hull (RH) is the hard cover protecting the grains of rice.
The B-RHA was crushed, ground, and sieved through a mesh number 60 (opening size 250 microns).
Thin sections were prepared to observe the texture, grain boundary, material components, and voids.
Grain Size and Distribution.
While the RHA content increases, the number of voids increase in the fired specimens at any firing temperature.

Moreover, the films have flat surface and small grain size. 1.
A large number of solvent evaporating accelerated the solution pH value further increased.
In the Fig. 3(b), due to adding the CTAB, the surface roughness improved to some extent, and grain size became smaller and uniform.
At the same time, the CTAB was found to can promote grain refinement.
Comparing to Fig. 4(a) and Fig. 4(b), with the increasing of the concentration of Zn2+, grain size is reduced, surface smoothness is improved.

Creep cracks propagated along grain boundaries decorated with M23C6 carbides and also sigma phase.
In addition to cracks and microcracks propagating exclusively along grain boundaries, Fig. 6, all samples also exhibited numerous cavities and interconnected cavities, occurring at grain boundaries, at triple points and very often at the interface of Cr23C6 carbides or s-phase with the matrix, allowing them to combine and accelerate creep damage, Figs. 7 to 9.
N is the number of cavities per unit area of the metallographic cut (cavities/mm )2 2.
Type K damage refers to cases with minor damage outside the main line of damage; Type C damage refers to cases with scattered cavity formations; at low levels of oriented cavitation (class 3a. lower limit), types K and C may be indistinguishable; Cavity chain = formation with several cavities at grain boundaries (HZ) extending into adjacent grains 3.
Initiation and also joining of cavities is facilitated by the precipitation of Cr23C6 carbides and also by the formation of s-phase, which plays a decisive role in weakening grain boundaries.

Table.2 Microhardness of the coating Sample The value of each test (HV0.1) The average value (HV0.1) Equivalent value (HRC) 572 911 1113 678 683.62 Cr3C2-NiCr 639.40 570.441 599.34 852.35 950.19 756.946 61.8 Grain-abrasion performance analysis.
Wear test experiment was done with MLS-225 wet sand rubber wheel grain-abrasion equipment.
Hard ceramic particles in the coating have good wear resistance property and could stop grinding crack expansion during grain-abrasion wearing process.
The extent of plastic deformation at the sample's surface is lesser than that of the sample after grain-abrasion wear.
The other is the number of hard particles in the coating.