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The result shows that the alternating magnetism promotes the austenitic grain growth of low carbon steel.
Fig.1 Grain in air cooling after hot rolling Fig.2 Grain in austenite region by alternating Fig.3 Grain in ferrite region by magnetic after hot rolling alternating magnetic after hot rolling Seen from Figure 1, the fine grain size under air cooling after hot rolling is about 12μm (10 grades)，the grain is coarse and uneven.
After alternating magnetic under austenite region, the grain is recrystallization coarse and even(Figure 2), the grain saw being more blunt and pearlier is uniform.
After alternating magnetic radiating (1T), the properties of low carbon steel has a influence on the microstructure and austenitic grain tends to uniform and lower angle grain boundaries. 2.
In the tensile test, mechanical properties is in accordance with grain shape and size, the grain enlarge and mechanical properties decrease less.

After determining the washed-out particles (and removing dust particles and residual adhered clay fractions), the samples underwent sieve analysis to evaluate the median grain size d50 and AFS (mean grain size number according to American Foundry Society, hereinafter referred to as AFS), including the construction and evaluation of granulometric curves.
For the AFS medium grain rating is valid, the higher the number, the finer the medium sand grain and therefore the smaller the size.
• Grain size influences the SiO2 content, with larger grains containing 1.1% more SiO2 than finer grains
Acknowledgement This research was funded by the project of MEYS (grant number CZ.02.1.01/0.0/0.0/17_049/0008399).
This research was carried out with the support of projects of student grant competition (project number SP2023/022).

This paper discusses the applicability of log-normal mathematical function to the calculation of hardness of materials which microstructure comprises grains with globular and lamellar sub-microstructural cells.
The possibility of calculating the hardness number using only geometric sizes of microstructural formations is discussed in this paper, where the grain is meant to be a container of the two most frequently occurred shapes in the microstructures – globular and lamellae.
Micrographs were subsequently analysed using Nikon NIS Elements software package and grain size (Dm), lamellae length (l), lamellae thickness (b), globula size (d) and α/β phase ratio were determined.
The grain size analysis in region 2, where α-phase is presented in the globular form, was done using EBSD method on starting alloy in order to establish the grain, lamella and globula size (Fig. 2, Table 1). 50 µm Figure 2.
EBSD map of starting alloy Grains of an alloy typically observed by light microscopy were in case of the starting alloy consist from the sub-microstructure cells formed of the globulas.

However, even for this material, significant changes of the porosity and grain structure are observed, where original grains of several µm diameter are divided into smaller grains of around 0.1 to 0.3 µm.
Pati of Combustion Engineering (C-E) and from Windscale hot laboratory on KWU fuels, observing significant number of µm size porosities at pellet rim [4].
Here "grain sub-division" is defined by observed fine grain formation and the definition does not include bubble formation nor swelling.
The sizes of the sub-divided grains are 150 to 200 nm which are the size range of the grains at the Cauliflower structure.
Number of cycles could be order of 104 to develop microstructures.

The {001}<110> textures transform to the {001} texture after cold rolling, in this process the grains divisional are analyzed by the HEXD result.
On the other hand, investigations associating with the deformed microstructure in IF steel sheet were focused on the substructure, e.g. subgrain size, orientation and configuration of the grains etc.
Fig. 2 the metallographic photos of different cold rolling reduction (a) 0%, (b) 20%, (c) 40%, (d) 60%, (e) 80% As shown in Fig. 2, it is can be found that the grains shape change form equal axis to elongate, when the reduction up to 80%, a large number of dislocations and sub-grains appear in some elongate grains, which demonstration the deformation in the grains is heterogeneous.
Fig. 3 the texture development of cold rolling Iron sample (a) 0%, (b) 20%, (c) 40%, (d) 60%, (e) 80% During cold rolling, three characters of the grains are distinct, grain shape, orientation and subgrain form.
The HEXD can provide the evidence of the grains break in the cold deformation process.

That is because the hard phase grains are tiny.
It can be found from the Fig. that the number of hard phase peering pits decreases.
Appropriate Carbon content refines grains, it makes the rim phase become thinner.
The number of binder phases among the rim phases also decrease along with the increase in carbon contents.
When the Carbon content is 0.8%, the grains of the cements are tiny and the distribution of binder phases among the rim phases is uniform; when the Carbon content is 1.2% the grains are the smallest and the number of the binding phases is at least.

In this work, we grew Al1−xScxN thin films with different Sc concentrations by changing the number of Sc tips which were set on the Al target.
Fig. 2 shows the relationship between x and the grain size of Al1−xScxN films.
And with the Sc concentration increases, the grain size of Al1−xScxN films decreases.
It is reasonable to consider that Sc may cause the Sc–N phases forming and enwrapping the AlN grains, which restrict the growth of AlN grains.
In our cases, when AlN films are doped with Sc, the grain size and Eg decrease.

The results of microstructure shows that the second phase particles pinned on grain boundary not only can inhibited the grain growth, but also the grain can be fined during the heating and cooling course.
The numbers of precipitates decrease greatly in the center of sample.
Fig.3 The particle pinning on grain boundary The effect of the second-phase particles on the grain refinement.
The second particles which are shown on the fig.4(b) is dispersed on the matrix and present irregular ellipse, but the numbers of second particles is less than that of on the fig.4(a) .
On the other hand, the ferrite grain can be fined during cooling by the second-phase particles pinned on the ferrite grain boundary.

Let us note that all images used in this paper bear the diamond pyramid imprints, which allow us to evaluate the microhardness numbers shown in Table 2.
Table 2 – Microhardness numbers and solid solution grain sizes.
Another type medium size particles are found on the grain boundaries around the recrystallized grains thus forming a network.
Comparing the two samples we may see that there is no correlation between the number of large and medium size particles and hardness.
The number of medium size particles is higher for sample 1 while their mean size is almost the same.

Finally, the load transfer between grains during yielding of the sample was studied.
This tensor describes differences between loadings for different grains.
During yielding, plastic deformation gradually begins for different grains leading to load transfer between groups of grains [1-3].
At the grain-scale, plastic deformation occurs due to slip on the crystallographic planes.
The dislocations are necessary for crystal glide, but if they are in an excessive number, they block each other and this leads to an increase of critical stress for the associated slip.