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There are a number of factors may influence the shape and distribution of basal texture, including rolling stress, deformation temperature, rolling passes, per pass rolling reduction, strip thickness, roll diameter, grain size (this refers to the original grain size), shear banding , second-phase particles and so on[6].
The grain structure was revealed after etching with a solution of picric acid (3g), acetic acid (20ml), distilled water (20ml), and ethanol (50ml).
The original microstructure of ZK60 alloy consisted of dentritic structure before rolling, shown in Fig.1 (a), warm rolling changed the shape of the grain and increased the grain boundary area[6].
Grain size and grain orientation distribution function affect the mechanical property of magnesium alloy with texture, the existence of texture results in the anisotropy of magnesium alloy sheet [7].
Dynamic recrystallization occurred during the rolling process at and above 350oC and fine recrystallization grains formed in the shear band area

The diameter of the primary α(Al) grains could be measured by the Image-Pro Tools and the shape factor could be calculated by using the formulas below [7]: (1) Where Ai represents the area of the primary α(Al) grains, and Di the equivalent diameter and d the mean grain size and n the number of grains, respectively.
The first solidified primary α1(Al) grains and the second solidified primary α2(Al) grains can be seen clearly from Figs. 5(a), (b), (c), (d)and (e), and the characteristics of the first solidified primary α1(Al) grains are tabulated in Table 3.
The primaryα1(Al) grains are near-spherical or rosette, as shown in Fig. 5.
For example, at the pouring temperature of 756°C, a small number of primaryα1(Al) grains can be found, as shown in Fig. 5(e).
But at the pouring temperature of 746°C, most of the primary α1(Al) grains are spherical or near-spherical, whose shape factor can reach 1.088 and average grain area can be about 687.09μm2, as shown in Fig.4(c).

The concentrated distribution of γ phase at grain boundaries hinders recrystallization and the tendency of grain orientation.
The low alloy γ phase precipitated at the grain boundary of the equiaxed grains can improve the grain boundary bonding force of the alloy, so as to improve the breaking strength of the alloy.
That means the grain boundary segregation of the alloying element is evident since the concentration of the alloying element at the grain boundary is higher than that in the lamellae grain.
It is difficult to find microcracks in the microstructure of the 1# specimen, while the other three samples all have a certain number of microcracks, of which 2 # samples have the most.
The addition of Cr strengthens the grain boundary while element Mo refines the grain and increases the content of γ phase.

Grain boundaries have been preferentially damaged in argon gas.
The average grain size was 55 µm in diameter.
Fatigue life was determined as the number of stress cycles at which a crack ran as far as half width of specimen from the notch root.
Their intensity was different between each grain.
A crack propagated mainly along grain boundary.

With the agricultural ontology, we can make a fine-grain price analysis.
Thus, how to make a fine-grain price analysis needs exploration.
In this paper, the production is the number of the advertisement posted by the real manufacturers.
From Table 2, we find that the number of the producing areas of an agricultural product is around 2.
With the agricultural ontology, we make a fine-grain price analysis.

Unlike HPT the minimal grain size after equal channel angular pressing (ECAP) reaches 200- 300 nm.
The number of anvils' rotations was as follows N: 0, 0.1; 0.2; 0.5; 1; 3; 5; 10.
HPT allows processing of samples with nanocrystalline structure, i.e. with the least grain size, which could be achieved in this alloy, applying SPD techniques.
The grain size here is less than 100 nm.
A heterogeneous structure is formed after 4 ECAP passes with the grains mainly elongated along strain direction with the cross-section of about 200 nm.

Typically these materials are composed of a so called grain/matrix structure with a maximum grain size of e.g. 3 to 5 mm.
Heterogeneities may be different refractory components, different mineral phases, grains and pores.
Flaw size may be expected to scale with the grain size.
The following "brittleness number", B is proportional to this ratio: EG L B F 
T⋅ ⋅ = 2 σ . (4) B is dimensionless.
Secondly, the contrast must not be excessive such that light grains are overexposed.

The equivalent grain size (globule size) is defined as the diameter of a circle with the same cross-section as the grain in section.
The total number of aluminum grains considered in the quantitative analysis was about 343,189 grains over 51 treatment conditions.
The grain coalescence takes place if two or more neighboring grains have low angle solid-solid grain boundaries or if the grains form coherent twins within the solid skeleton in the semi-solid state.
The grain coalescence mechanism is usually used to rationalize the rapid or unexpected grain growth during the soaking experiments.
In this sense, our results are in agreement with Arnberg et al.[9], who reported that the MHD cast ingots were found to have a high fraction of grains having low-angle and twin grain boundaries than the grain refined alloys and thus undergo fast grain growth through simultaneous agglomeration/coalescence and Ostwald ripening.

A very weak effect of austenite grain size on packet size was found. 2.
Grains with high-angle boundaries do not significantly grow after tempering; on the contrary, low-angle grain boundaries move, fully justifying the hardness evolution with the tempering temperature.
The austenite grain size was measured according to ASTM E112.
Packet size versus austenite grain size.
On the contrary, grains with low-angle grain boundaries (cells) move.

In the next part, the influence of the number of passes on the strengthening curves was evaluated.
At this temperature, the total number of 4 passes was applied in dependence on the development of extrusion.
The alloy structure after the fourth pass through the ECAP tool with helix matrix of 30° shows a fine-grained structure with a mean grain size of 1 mm to 2 µm, and high disorientation between the grains (see Fig. 13 a, b).
The main aim of the experiments was refinement of the structure of selected magnesium alloys with using the minimum number of passes through the ECAP forming tool.
The alloy structure after the fourth pass through the ECAP tool shows a fine-grained structure with a mean grain size of 1 mm to 2 µm, and high disorientation between the grains (see Fig. 13 a, b).