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First: macroscopic, covering a wide number of grains.
Second: structural micro-stress, located in a grain and its surroundings.
Experimental X-ray diffraction and section compared with blind hole methods Results The Fig. 4, shows data of experiment analysis of micro-deformations under grain size area it was used X-ray diffraction and the stress average value from -40 MPa to -187 MPa.

They have investigated the grain size, dislocaction density, strain, interplanar distance, miller indices, number of crystallites per unit area and lattice constants of CdS nanostructures, and analyzed the thickness and optical properties transmissions, energy band gap, refractive index and optical dielectric constant where proved distinguished results compared with other ones.
Spin coating Speed (rpm)/(sec) Peak 2θ FWHM Grain Size (nm) Dislocaction density (δ) (1014 lines/m2) Strain (10-3) Interplanar distance (d) (Å) Miller indices (khl) Lattice constants a and c (Å) Thickness t (nm) 1000/30 29.63 0.82 2.77 0.1303 0.130 1.557 321 a=1.038 4.015a 2.35b c=3.12 6.545a 7.04b 80 3000/30 26.28 21.58 1.168 216.7498 5.3280 1.7794 310 a=1.186 c=3.558 60 5000/30 29.56 0.48 3.78 0.0699 0.0956 1.5608 210 a=1.040 c=3.121 40 Ramaiah et al. aRef. [7] Exp.; Lahewil et al. bRef.; [9] Exp.
We determined that all samples surfaces are relatively smooth and uniform, having well defined nanosized grains with relatively small roughness values.

Hegemana illustrates the relationship between the surface roughness and the grain size during grinding on cobalt tungsten carbide composite materials [6].
The smaller grain size, the wear resistance is higher.
When the grinding depth increases, the maximum undeformed cutting thickness of single grain will increase, and the number of abrasives increases in per unit grinding area.

The stresses versus number of cycles to failure (S-N) curves were plotted after each test to demonstrate the fatigue strength of samples.
The microstructure contains large and small twinned grains and dark globular eutectic particles dispersed which is typical of copper alloys [5].
Parallel straight lines extending across many of the grains are called annealing twins and they usually appear when a metal has been mechanically worked at a high temperature and deformed [6].
Ketabchi, Enhanced properties of nano-grained pure copper by equal channel angular rolling and post-annealing, Materials & Design, 34 (2012) 483-487

The grain size was estimated by using Scherrer formula.
The effective permeability μe was estimated through the formula : L is the inductance (H), Le is the length of effective magnetic path, Ae is the effective cross-sectional area and N is number of turns.
As pointed out by Herzer [7], the grain α-FeSi of nominal composition Fe73.5Si13.5B9Cu1Nb3 has a mean diameter of about 10-15nm after annealing treatment at 500-600℃.
Our result indicates that, partial substitution of Fe for Co may lead to the decrease of nucleation rate of Cu and the increase of grain size as the result.

The crystal nucleus of nitride is large and distinct, and grain-boundary among crystal nucleuses is a little lower than the center section of crystal nucleuses.
Some 'concave ditches' of crystal nucleus interface are filled in and the number of crystal nucleus is less than Fig.1 (a).
The reason might be that some new crystal nucleus of TiN film deposited by PVD would be nucleating and growing up on the initial grain-boundary of TiN permeation layer with which initial concave ditch can be filled up.
It can be seen that the crystal grains are very fine.

Based on the VCFEM a number of numerical methods were developed by Ghosh et al. [8,9] to analyze the effects of cracks into composite materials.
In the numerical simulations a volume increase of zirconia grains of 3% [1,11], as consequence of the t→m phase transformation, was taken into account, neglecting the lattice distortion.
Results The stress intensity factor (SIF) for a crack located in the alumina or zirconia grains, was calculated by analysing mixed VCFEM models containing heterogeneous hybrid elements and elements with cracks, as shown in Fig. 3.
The graphs clearly show that the thermal load reduces the stress intensity factor KI, which is due to a residual compressive stress in the alumina grains, while a strong increase is observed when the zirconia t→m phase transformation is taken into account.

Introduction Titanium carbide (TiC) thin films have been extensively used in many applications due to a number of special properties, such as very high melting point, high hardness, thermal and chemical stability, excellent wear resistance, high oxidation resistance, and a low friction coefficient.
The defect, impurity and grain size are the important factors which made the difference of the microstructures of thin films.
The film with less thickness may possess generally more defects, impurity and less grain size, which reduce the TC.
In fact, there are a lot of factors such as component, phase state, interfacial thermal resistance, surface contamination, defect, grain size and so on, which will exert effect on the TC of the films.

Table3 The mineral component and volume percentage of the mould powders[%] sample melilite glass phase A-1 2-3 97-98 A-2 — 100 A-3 — 100 B-1 40-45 55-60 B-2 25-30 70-75 C 3-5 95-97 The texture of the residue membrane numbered A-1 is a classical crystal-glassy two layers with clear lines, and the rate of crystallization is 2%～3%.
Most of the melilite is interlacing, radial and head to head shaped, the grain size vary in size, generally is 0.068mm～0.166mm, the maximum one is 0.391mm, some erosion texture of melilite appear in the mould powder.
Most of the melilite is formed as interlacing, head to head and radial shaped, and the grain size is 0.049～0.38mm, some melilite crystallite appeared.
The melilite is formed as interlacing, head to head shaped, and the grain size in fine, general is 0.035mm.

As can be seen from Fig.1a, the thickness of the as-rolled NiTi sheet ranges from 90μm to 100μm, and it is difficult to identify grains boundaries due to refined grain sizes.
It is seen that the microstructure of the NiTi specimen is sufficiently homogenous with fined grains ranging from 50nm to 100nm.
It is seen that the critical stress of specimen increases with the increasing number of loading comparing to the former cycle, which is due to the strain-hardening by formation of high density of dislocations during tensile deformation cycle.