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The undoped ZnO film is very rough and composed of fine grains on the surface.
Whereas, in the case of x=0.05, the film shows a smother surface consisted of much larger grains than the undoped film.
A film consisted of larger grains is more likely to have a narrower mosaic distribution and better crystallinity than one consisted of smaller grains in which the number of grains that may be misoriented is larger, supposing all other conditions are identical.
We, therefore, speculate that the superior atomic alignment of the film of x=0.05 is associated with the larger grains compared with the other films composed of smaller grains.
We speculate that the superior epitaxial growth of the film with an optimum Mn content is associated with the microstructure showing much larger grains than the other films.

With nearly 10 years of oil and gas transportation project construction, a large number of X70 steel is used in engineering construction[1-3].
Its microstructures are fine ferrite grains ,which is slightly elongated along the rolling direction.
Compared with the original metallographic microstructure, the grains of the fusion zone, overheated zone and recrystallization zone is grown up a little.
Microstructures of recrystallization zone both have underwent grain nucleation and growth.
Because the temperature of recrystallization zone is relatively low and grain growth is not significant, so it forms uniform composition and fine ferrite grains after recrystallization.

The microstructure consists of a fine-grained (approximately 2 - 3 µm) duplex microstructure, i.e. globular γ grains with a small volume fraction (approximately 25%) of lamellar grains and some α2 at γ-grain boundaries.
The grain distribution is comparatively random perpendicular to the extrusion direction.
Lamellae interfaces are roughly parallel to the extrusion direction. γ-grains are the same size in both longitudinal and transverse sections, whereas lamellar grains are larger parallel to the extrusion direction.
These investigations show that the numbers of twinned grains are the same in both the as-received state and after the TMF loading, even though twinning is known to be an important deformation mechanism in TiAl [10-13].
The mean grain areas after TMF loading were considerably smaller by a factor of 3-5 [14].

Alloys of zirconium are of considerable importance to the nuclear industry, and there has been considerable effort over a number of years to characterise the effects of texture on the mechanical behaviour of this material [4-7].
Grain family elastic strains were extracted from the data by applying single peak fitting to monitor diffraction peak shifts.
Grain orientations were then attributed weights to match this texture using the popLA texture analysis suite.
This strain corresponds to the initially small number of grains oriented with the basal pole parallel to the in-plane direction.
As twinning progresses, the population of these grains increases.

So, if you want to model crack incubation (near a critical point), you don’t have to worry about accuracy representing how every atom or every grain in solids interacts with the neighbour grains.
Imagine a hundred grains simulated with matchsticks arranged along a line.
The length of these matchsticks measured grain fitness is a random numbers simulated with Monte Carlo methods and are between 0 and 1.
First, the grain with the lowest fitness goes broken.
Run on a computer, the models crack propagation are distributed by size – the number of grains involved in chain event – in much the same way as in real cracks initiation and propagation.

Introduction The development of superalloy is from equi-axed grain to directionally solidified to single crystal superalloy.
da/dN=K·(DKε)n (1) Where: a is half crack length, N is cycle number, K,n are empirical constants relative to TMF cycle.
Bizon, R.L.Dreshfield, and F.D.Calfo[4] founded that TMF strength of directional solidified Nickel superalloy was higher than that of equi-axed grain superalloy with the same compositions, for the lower elastic modulus and absence of grain boundary in landscape orientation.
For equi-axed grain, directionally solidified and single crystal superalloy, there were no differences in composition and intragranular microstructure.
A number of studies had shown that single crystal superalloy’s TMF life was relation to elastic modulus.

The number of thermal shock cycles was recorded.
But when the fiber content exceeds 15 wt %, porosity is relatively high owing to a large number of micro-cracks in Al2O3 ceramics.
Grain nucleation and growth of both ZrO2 fiber and Al2O3 matrix can be seen from Fig. 5.
The crystal grains develop well and the structure of Al2O3 ceramics is compacted.
The glassy material is formed in grain boundary, which makes the grain boundary is not obvious.

In SEM studies there is also the added problem of grains growing up from the hidden bulk sample below the surface.
The high transmission and photon flux allows the reflections from individual crystallographic grains to be detected, and specialized software allows these reflections to be indexed back to the individual grains, thus allowing individual grains to be followed in-situ.
This results in an inhomogeneous grain size distribution with an average grain size of about 500 µm.
To avoid spot-overlap (different sample volumes diffracting into the same position on the detector), it was decided to limit the number of grains intersected by the X-ray beam penetrating through the sample.
Adams: Orientation Imaging Microscopy: Application to measurement of grain boundary structure (Mat.

While the grains in smaller size are reduced and the size is much more even.
When the ratio of salt is increased to 4:1, the grain size will also become larger.
Due to smaller growth space, the grains are frequently collided between each other.
Therefore, the grain is developed incompletely and the size is smaller (figure 3(c)).
Acknowledgements This paper is supported by National Natural Science Foundation Project (grant number:70471045) : Study on sulfur fixing mechanism of compound sulfur fixing agent to coal oxygen-enriched combustion.

Surface integrity was described by macroscopic residual stresses, microstrains, grain sizes and phase composition.
Microstrains e and grain sizes D averaged over all values in areas 1, 2, 3 and both directions are in Tab. 3.
Microstrains e and grain sizes D averaged over all values in areas 1, 2, 3 and both directions.
Although debatable and problematic, the average values of microstrains and grain sizes reflect the essence of the individual results which is that no significant differences in both measured directions were observed and that area 1 had distinctly lower values of grain sizes. 7.
· The average grain size (Tab. 3) is the smallest in area 1 and it rises with increasing tool tilt, i. e. in the areas 2 and 3.