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However, the dimension of these notches is in the same order as the grain size.
The average size of the grains is approximately 30 µm.
The notch depth developed through the micro-milling process is smaller than the grain size.
The ultimate number of cycles was 107.
The numbers of run-out specimens per state are given in Fig. 4.

The change of the number and morphology of β-Mg17Al12 phase results that the β-Mg17Al12 phase is turned from continuous network structure into intermittent-like and granular structure.
Therefore, the number of precipitation β-Mg17Al12 in No. 2 alloy after T6 heat treatment is greatly reduced than that of No.1 alloy, as shown in Fig.2(b).
The Al2Y and Al2Gd phase effectively hinder the barriers across the grain boundaries, preventing grain boundary sliding and migration.
At 200˚C, Al2Y and Al2Gd compounds can be used to stabilize the grain boundaries and prevent grain boundary sliding, which, in turn, significantly improved the thermal stability of alloys.
The tension crack tends to extend along the continuous, fragile grain boundary of the β-Mg17Al12 phase, which, in turn, results in the cracking between grains.

It can be seen that the microstructures of steels are composed of polygonal ferrite and pearlite, the grain size number is 10.
These particles which can hinder the motion of dislocation upon deforming and bring grain bounbary strengthening precipitate in ferrite or along grain boundary.
In this test, a large number of dispersive-fine carbonitrides are found in ferrite and along grain boundary, which can increase the strength and improve the impact energy of steel by hindering the migration of austenite grain boundary, refining grain size and precipitation strengthening.
The ralationship between mechanical properties and grain size is expressed as Hall-Petch equation[4].
In this test, the microstructures of experimental steels are composed of polygonal ferrite and pearlite, the grain size are very fine, compared with vanadium-free steel, Adding vanadium does not change the microstructure and grain size of normalized steel.

When the sample annealed at 350℃ for 5s, the first recrystallized grains were observed in the vicinity of the grain boundary.
A large number of fine secondary particles in the as-homo specimen was formed in the Al matrix due to the effect of the homogenization treatment.
It can be seen that large deformed specimen with fine recrystallized grain are recrystallized faster than low deformed specimen with coarse grains.
In generally, the metal materials cause an increase in dislocation density and a decrease in crystallite size during deformation, and a large number of HAGB and LAGB are generated as the reduction rate increases.
When primary recrystallization is complete, the structure is not yet stable, and further growth of the recrystallized grains may occur by the migration of grain boundaries with the grain-boundary free energy as the driving force.

It is difficult to control the increasing number of variables because more and more new materials are added into the concrete, along with new properties to be considered.
The high performance concrete usually involves a low w/c ratio has a high content of unhydrated cement grain.
The hardness of cement grain is nearly 10 times higher than that of hydrated C-S-H gel, as shown in Table 2.
Therefore the phases with penetration depth in the range of 0 to 100 nm are preliminarily determined as cement grain, and the phase corresponds to the slope beside the cement grain along with a rapid increase rate of penetration depth is the interface.
Then the HD C-S-H gel gradually forms in the gap between the unhydrated cement grain and the LD C-S-H.

Microstructure analysis such as size, shape and number of precipitates were studied by Optical microscopy (OM) and Scanning Electron Microscopy (SEM).
The change in number of CuNi precipitates and CuNiZr precipitates led to an increase in hardness and wear resistance.
XRD analysis reported the reduction of β phase and showed that the grain size of ⍺ phase and β phase were refined.
It was found that grain size of CuBeZr alloy was not changed after DCT process and the average is around 36µm.
However, bigger average precipitate size at longer immersion time caused by more number of big precipitate developed.

Each cell has four state variables: (a) dislocation density: the initial dislocation density of cell is taken as the dislocation density after deformation; and the static recovery and recrystallization make the dislocation density reduce; (b) grain orientation: the new generated recrystallization cell is randomly given number between 1 to 180 as a orientation value.
The same orientation value belongs to the same grain, and different grain is corresponding to different color; (c) recrystallization flag: “0” indicates un-recrystallization state, and “1” indicates recrystallization state; (d) grain boundary sign: it is used to indicate the location of grain boundary cell.
The fraction of static recrystallization can be expressed as follows: (13) where, is the cell number for static recrystallization, is the total cell number for cell space.
The temperature is 1200 ˚C, the initial grain size is about 110.
In Fig. 1(a), the initial grain of un-recrystallization is logoed with gray, and the multicolor grain represents the new generated dynamic recrystallization grain during the first pass deformation, the fraction of dynamic recrystallization is 8.1%.

The cast materials have an equiaxed grain structure with an average grain size of ~140µm, and constituent particles are mostly decorated in the interdendritic regions and grain boundaries [10].
Characteristic size parameters of constituent particles, equivalent diameter d and number density were measured by the image analysis software Image-J.
This is expected since the C1-3 samples have a weaker potential for concurrent precipitation and have limited number of pre-existing dispersoids.
A large number of recrystallized grains, with equiaxed shape, are already present after a short annealing time of 500s.
As these recrystallized grains are growing, their close to equiaxed shape further confirms that the recrystallization process is only weakly affected by the pre-existing dispersoids and concurrently precipitated ones, both of which are limited in number.

Bending angle increased as grain size increased and it jumped up when grain size exceeded the foil thickness and then became constant.
Laser device Q-Switch pulsed YVO4 Wave length [nm] 1064 Frequency [kHz] 200 Laser power [W] 2-14 Laser scanning velocity [mm/s] 10 Scanning number 1 Forming atmosphere Ar Next, effect of grain size on bending angle was investigated.
Effect of Grain Size.
Effect of grain size on bending angle is plotted in Fig. 7.
(2) As grain size became larger, bending angle also increased when grain size was smaller than the thickness of foil.

With this level of moisture, the grain is susceptible to deteriorate rapidly.
Further, surface temperature of grain was measured using an infrared thermometer.
Air Rough rice grain T (oC) RH v (m/s) Mo(d.b.)
In this experiment, it was found that in a sample of 30.4 g of rice (BRSMG CONAI), 52 hours after drying, the number of grains presenting cracks and fissures increased from 2.73% to 8.9%.
Moreover, short-grain rough rice was very susceptible to fissure whereas long-grain rough rice with a high amylose content was much more fissure-tolerance.