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There are two types of grains; 1) large grains (LG) with an average size of 1.4 microns and 2) the small grains (FG) with an average size of 0.5 mm.
It is also known that the number of present particles, their size, distribution pattern and interparticle distance, as well as the irregularity degree of the matrix lattice and precipitation have an effect on the material dispersion strengthening [2].
Type 1 grains are sized within 0.1-0.5 µm (let us denote them as small grains, SG).
Type 2 grains are sized within 0.5-4.0 µm (let us denote them as large grains, LG).
The total number of Ti3Al and TiAl3 phases in the I-region is 3% of the volume of material and in the II region - 10%.

With the social and economic development of our country, in particular, a number of large-scale hydraulic and hydropower projects to be built during the development of the western region, as a type of filling material, rockfill material will be more widely used in the high rockfill works [1].
Characteristic of grain breakage Measurement of grain breakage.
This indicates that the vibration process during sample preparation mainly cause breakage of large-sized grains to increase the proportion of fine grains; despite the small amount breakage of medium-sized grains, the breakage of large-sized grains may supplement these decreased medium-sized grains.
Grain breakage caused by triaxial test.
(3) During the shearing process, the breakage of grains in rockfill materials mainly occurs on the surface of grains with diameter between 20~60 mm, and most grains break into fine grains with diameter under 10mm.

Cooperative Grain Boundary Sliding and Shear Banding at High Strains in Ultrafine Grained and Nanocrystalline Pd Alloys.
In cg specimen a grain refinement occurs whereas in nc one – the grain growth. 4.
These in-grain accommodation processes occur in non-correlated manner in adjacent grains leading to formation of cracks and voids in sliding grain boundaries.
Secondly, a number of grains retarding the band formation experience intragranular slip [19-21].
Vol. 18 (1983), p. 582 ], which is necessary to form enough number of CGBS bands to maintain steady plastic flow [[] A.I.

Novel Approaches to the Thermodynamics of Grain Boundaries and Grain Boundary Junctions Lasar S.
Three recent investigations in the field of thermodynamics of grain boundaries and grain boundary junctions are presented. 1.
Expressing µ through the thermodynamic characteristics of the volume of the grain and taking into account that 0s s as s= Γ , where sas is the surface excess of the entropy per atom at the boundary surface we arrive at [11] ( )0 0 s v a a a d s s dT dp γ= −Γ − − Γ Ω (3) A grain boundary separates two thermodynamically identical phases, and one peculiarity of grain boundaries consists of the fact that for a system with a grain boundary the number of degrees of freedom is by one greater than for an interphase [10], which is completely determined at constant temperature.
The three line tensions of the three grain boundaries are indicated in Fig. 3 by γi-j with the indices i and j denoting the two grains on both sides of the grain boundary.
For an equilibrium grain size, if it exists, the derivative d G d ∆ S must equal zero at T = const ( ) ( ) ( ) 2 2 2 2 0 2 2 2 sold G c d cdc dc d G V c d dc d dc d γ γ ∆∆ = + + S S S (11) grain 1 grain 2 grain 3 grain 1 grain 1 grain 3 grain 2 grain 3 grain 2 For positive grain boundary energy and positive adsorption ( 0Γ > ), when the concentration of impurities at grain boundaries is higher than in the bulk, the derivatives ( ) ( )22 2 2 2 , , sold G c d cdc dc d dc γ ∆ S in Eq. (11) are negative.

With the change of the average grain size, d, in the 1nm…1cm interval the grain structure, the grain boundary structure and defect structure of grain volumes are changed.
In some intervals of grain sizes, the grains remain dislocation-free.
The grain consists of (1) the grain body, (2) grain boundary, (3) triple junction and (4) quadrupole node.
Grain boundary migration and grain growth occur during plastic deformation of ultra-fine grained FCC metals [15].
Deformation at the yield stress and in the interval ε = 0…5% is provided by grain boundary gliding and emission of small dislocation groups (number of dislocations n does not exceed 5) in the largest grains with cells and fragments (see Fig.6b, the darkened area).

Grain refinement.
However, understanding of the mechanism of the grain refinement process is still an open problem.
High-pressure torsion(HPT) is one of the methods highly suitable for experimental and theoretical studies of formation of the ultra-fine grain substructure: very high strain can be achieved without interruption and one can look at various amount of strain in one specimen.Due to relatively simple loading conditions strain can be defined approximately as simple shear.The large number of recent publications reviewed in[1,2] indicates that the research is still mostly empirical.
The basic assumption is that the lattice rotation is impeded in grains mostly near grain boundaries.
On the other hand,the observed non-equilibrium boundaries are wider than δ≈10-9 m of standard grain boundaries.

The white areas are the smallest grains, filtered out because considered to be more likely γ' precipitates than γ grains.
The average grain size is 10µm and the GOS is very low in most of the grains.
The initial grain size was in the range of the limiting grain size that can be calculated based on the Zener model [5].
In this case, abnormal grain growth is due to grains having enough difference in stored energy with the neighbourhood, thus triggering strain induced grain boundary migration across secondary phase particles.
According to Pande's model [6], the number of twins per grain is increasing with the distance over which grain boundaries have moved (i.e. grain size), and with the grain boundary velocity, which itself is usually decreasing when increasing grain size.

Peasant household family characteristics include family initial land amount and migrant workers number.
The higher migrant workers number means the family has little surplus labor.
The higher the farmland comprehensive fertility, the higher yield the grain, the less possibility to outflow land.
Tieling city is located in northern Liaoning province, has rich agricultural resources, known as the granary of northern liaoning province, has four national commodity grain base counties, national major grain producing areas, national key commodity grain production base, high quality agricultural products production and processing bases[9].
Because of lacking labor force engaged in agricultural production, the more migrant workers number the family, the more possibility to outflow land.

Details such as misorientation angle, inclination angle, GB plane, CSL value (∑), simulation box size and number of atoms are mentioned in table 1 and table 2 for STGB and ATGBs respectively.
Tilt axis GB plane (hkl) Sigma (∑) Misorientation angle (θ) Simulation Box dimensions Number of atoms 1. <110> <111> ∑3 70.53° 66.16x265x99.24 97,636 Table 2 Configuration details for four ∑3 asymmetric tilt grain boundary tilted along <110> with θ=70.53°.
Inclination angle (Φ) GB plane(s) (hkl)1/(hkl)2 Simulation box dimensions Number of atoms 1. 15.79° <221>/<447> 65x330.8x99.24 1,19,848 2. 29.50° <11 14>/<332> 68.3x264.8x99.24 1,00,532 3. 54.74° <221>/<001> 65x272x99.24 1,00,702 4. 76.74° <445>/<227> 66.4x265x99.24 97,847 Results and Discussion Asymmetric tilt grain boudaries were generated in LAMMPS using the methodology described in Fig. 1.
Fig.1 Schematic for generating asymmetric tilt grain boundary.
Ab initio calculations of grain boundaries in bcc metals.

The results about the grain numbers at different locations can be seen in Table 4.
Those are the grain numbers in the simulated region 1024×1024 (W0).
Table 4 Grain numbers in the simulation calculated based on the experimental results Pouring temperature/℃ Grain number edge R/2 center 630 32 76 173 690 10 18 21 Results and Discussion The simulation and experimental results about the microstructure at the three positions in the slurry under the pouring temperature of 630 ℃ and 690 ℃ can be seen in Fig. 2.
Combined with the experimental and simulation results, it can be inferred that the number of nucleation directly affects the growth space and morphology evolution of grain.
The morphology of grains also can be changed from dendritic to equiaxed or even spheroidal by other methods such as adding refiner to increase the number of crystal nuclei.