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Determination of Rock Hardness number Vickers Hardness Number of Rock (VHNR) of the samples were obtained by multiplying Vickers Hardness Number VHN (kg/mm2) with amount of minerals expressed by Equation 5.
VHNR = i=0nVHNiAi (%) (5) VHN is Vickers Hardness Number (kg/mm2), A is amount of minerals and n is number of minerals 2.6.
Avarage Grain Size of Selected Rock within S/W Nigeria Rock Samples Average grain size (mm) Average grain size (mm) Average grain size (mm) Average grain size (mm) Average grain size (mm) Medium Feldspar-Granite 0.12 0.12 0.13 0.13 0.14 Coarse Muscovite-Granite 1.04 1.02 1.04 1.02 1.04 Biotite- Hornblende Granite 0.67 0.66 0.69 0.69 0.65 Table 3.
It could be inferred that lesser holes and depth were drilled on medium feldspar granite, this could be due to low grain size and high rock hardness number of 0.12 – 0.14 mm and 821.64 kg/mm3 respectively.
This could be due to low grain size, high quartz content and high rock hardness number of 0.12 – 0.14 mm, 51.35% and 821.64 kg/mm3 respectively. 4.

The substructure of a single grain in an electron backscatter diffraction (EBSD) data map is studied, focusing on the influence of the grain boundary configuration on the misorientation to the average grain orientation of data points close to the grain boundary.
These orientation variations were attributed to grain-grain interactions.
and a small number of misorientation boundaries (low mean θptp) or to fragment boundaries having higher misorientations (high mean θptp).
Depending on the orientation of the boundary plane (which can not be characterised by 2D EBSD measurements of plane sections) and the misorientation axis between the crystallites a number of misorientation angles that minimise the surface energy of the boundary can be found.
Sutton and Vitek [6] suggest that the boundary will split up in a number of shorter sections having misorientation angles that are alternately higher and lower than the average misorientation angle.

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.

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.

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.

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.

The solute segregation to grain boundaries may be classified into equilibrium and non-equilibrium segregation.
Introduction Material grain boundaries comprise of narrow zones of weakness.
When failure occurs in material, it often occurs catastrophically by fracture along grain boundaries and often by the micro-segregation of embrittling impurity to these grain-boundaries.
Data group number M input Data of group i input Atom percent of each element calculation and output Withdraw from the system Average atom per cent calculation and output Are the data right?
McLean, Grain-Boundaries in Metals, Oxford University Press, UK (1957)

The Study of the Electrochemical Graining Process in NaBO2- H3BO3 Solution and Grain Appearance on the Surface of Aluminum Alloy Jun Q.Liu 1, a, Xiao H.
The mainly process of electrochemical graining on 6063 aluminum alloy included graining at alternating current, anodizing and chemical coloring.
To quantitatively assess the process effect of graining, four score indexes were self-established, which were grain density (grain numbers/sample width), grain width, grain depth and grained color: (1) Grain density (ρ): the best range was 6cm-1≤ρ≤10cm -1, the second, 4cm-1≤ρ≤5cm-1 and 11cm-1≤ρ≤13cm-1; (2) Grain width (w): the best range was w≥280µm, the second, 200µm≤w<280µm; (3) Grain depth: enough depth was the best; (4) Grained color: the best was silvery white after treated, the second was gray.
According to the above process parameters the grained effects were as follows: grain width was 280µm, grain density was between 8cm-1and 10cm-1, grain depth was remarkable, and color of all grained samples was silvery white.
Observation of the Grained Morphology.

This paper deals with the influence of the coarse aggregate grain size on the frost resistance of concrete.
Frost resistance of concrete is influenced by a number of factors with a significant part of them being related to the composition of fresh concrete.
Results and Discussion Fig. 1 presents the results of RDM in relation to the number of F-T cycles.
The higher the maximum aggregate grain size, the better the resistance of concrete to cyclic freezing.
The smaller the maximum grain size of the used coarse aggregate, the lower the frost resistance of concrete.