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This softening is observed in a large number of metals and alloys and for numerous deformation processes.
During deformation, as the grains develop by nucleation and growth, the average dislocation density drops, leading to significant softening.
The commercial composition material has a stabilized microstructure with a grain size of about 100µm.
Acknowledgment The authors gratefully acknowledge the UK EPSRC (Engineering and Physical Sciences Research Council) for their financial support under grant number GR/R70514/01.
RISØ international symposium on annealing processes: recovery, recrystallisation and grain growth (1986), pp. 167-187

Basic Equations of Scattering Field For simplicity, we discuss a sand grain with electric charge as Fig. 1.
In this theory, the intensity of a sandstorm is evaluated by N in particle number/ 3 m and/or by the optical visibility bV in m.
(21) Here, the symbols "Im" indicate the imagery part of a complex number or function.
Conclusions An analytical formula for attenuation of the scattering from the modeling is obtained in this paper, according to which the effect of electric charge of sand grains on the propagation is quantitatively discussed.
Meanwhile, the effect of sand grain size, permittivity, visibility, amplitude of incident electric field, frequency, etc. on the scattering attenuation is quantitatively displayed also.

In the case of Al 5483 alloy the microcrystalline and ultrafine-grained samples were tested.
HE processing resulted in the reduction of the cylindrical ingot diameter from 50 to 12 mm in one pass and subsequent decrease in the average grain diameter from 51μm to 130 nm.
The camera was synchronized with the test driving signal and registered images of samples surfaces at the maximal force every 200 or 500 cycle for microcrystalline and ultra fine-grained samples, respectively.
Acknowledgements This work was financially supported by Polish Ministry of Science and Higher Education (contract number 0044/IP2/2011/71).
Kurzydlowski, Investigation of fatigue crack growth rate of Al 5484 ultrafine grained alloy after ECAP process, Phys.

The agglomeration can be affected by two factors, such as instability between particles during the preparation and synthesis process due to increased surface tension between grains in the particles.
The surface tension between particle grains is caused by the small particle size, so the surface area becomes large, resulting in the instability of the nanoparticles.
These bonds will create grains agglomeration of particles [11][12].
The large grain size in iron sand can be caused by a large number of impurities, such as minerals (Mg, Al, Ti, and Others), which envelop the magnetic part of the particles, resulting in a low percentage of dissolution of non-magnetic minerals.
By the Rector’s Decree Number: 0188/UN9.3.1/SK/2023, On April 18, 2023.

Figure (a) and (b) show that the main microstructure is ferrite, along with a tiny pearlite or bainite located at the ferrite grain boundary.
Figure (c) shows that the microstructure was F + B, Figure (a), (b) and (c) shows that ferrite grain size closes to the average grain size, which can reach to the grade 9 around.
Figure2(c), (d), (e) shows the microstructure of E11, figure (c) shows pearlite that located in ferrite grain boundary, figure (d), (e) is the microstructure of bainite.
The means ferrite grain size of E11 approaches that of E12, but pearlite of E11 is tinier, which also contains a small amount of fine bainite, so it shows higher BH and BHT value.
Plastic deformation can increase the dislocation density and the number of subgrain of ferrite and the cementite that is in the pearlite, promote cementite spheroidization, improve yield strength, tensile strength being baked , therefore pearlite is good for bake-hardening value to improve.

When the argon/oxygen ratio is 9/1, the surface is most smooth and the largest grain is obtained.
A number of atoms deposited on the substrate at the short time, which easily causes that atoms is not sufficient time for diffusion, recombination, and prone to reunion.
Although the sputtering ratio with the increase of argon/oxygen ratio increases due to the rise of argon content, the number of oxygen atom decreases, which prompts the improvement of sample’s quality.
The distance of crystal space increases with the increase of sputtering power, but the grain size firstly increases and then decreases.
Both the Crystal quality and grain size increases, which reduces the scattering attenuation and increase the carrier mobility.

Each layer consists of columnar grains [6-11].
The two side layers consist of near-equiaxed grains [1-5,12].
The grain indicated by “x” might be a recrystallized grain.
In Fig. 4B (middle area), the number and size of the dark areas decreased, and the dark color became brighter.
The number and size of the dark areas in Fig. 5 are greater than those in Fig. 4.

As shown in Fig.2, SFAW, same as the common grinding tools, consists of abrasive grains, bond material and pores.
What makes different between common grinding tool and SFAW is that the adhesion between grains and bond material in SFAW is relative weak.
When a larger particle emerges on the SFAW surface, grains surrounding the larger particle can be forced to move for adjustment.
It indicates that the PFC model for compacting process of SFAW workblank is valid to study the regular pattern and reduce the number of practical experiments in some certain.
It indicates that the model based on particle flow method for compacting process of SFAW workblank is valid to study the regular pattern and reduce the number of practical experiments in some certain.

However, two of the main problems for industrial applications are the low formability and the high directional anisotropy of these alloys, which are caused by insufficient number of active deformation systems.
The microstructure of the bar shows a mixture between fine-grained structure with an average grain size of 3 µm and long stretched grains in extrusion direction.
The pan-cake shaped grains are the just stretched (non-recrystallized) structures of coarse grains existing already in the casting billet which was used for the extrusion.
These elongated grains have a length of about 300 ~ 700 µm.
This work has been funded by the German Ministry of Education and Research (BMBF) under the contract numbers 03BRE8CL and 05KS1MCA/2.

The grain morphology was investigated before the creep test by DM8000 Optical Microscopy (OM).
Before creep tests, the grain morphology of the FGH96 superalloy was observed by OM (Fig. 1a), and the grain size was in the range of 20 μm~30 μm.
Since the solution temperature was higher than solvus-temperature there was no primary γ’ precipitate located at the grain boundaries.
Besides, FGH96 superalloy belongs to Ni-based alloy similar with many FCC alloys, there were a large number of annealing twins (‘special boundary’ Σ3, where the Σ3 coincident site lattice is a 60°<111> grain boundary) due to the low stacking fault energy in this alloy.
There were a large number of secondary γ’ precipitates with a size of 100 nm~200 nm and tertiary γ’ precipitates with a size of 10 nm~20 nm.