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Although the figure is monochromatically printed, the grains with a dark half tone have orientations around (0001) plane, not those around {10 _,10} planes.
Number of grains with bright contrast was increased compared with Fig. 3 (a), the orientation of which are near {2__,110} planes.
There are the grains having around {10_,10} planes are also observed, although the grains can not be distinguished from those having around (0001) plane.
In the previous study [1], grain refining occurred during the wavy form pressing, but in the present study, fine grains were not observed, and many twins were observed as shown in Fig. 4 (a).
There are few fine grains with bright contrasts in both the specimens, showing recovery occurred in these specimens but recrystallization was not accomplished yet, even at 723 K.

The formation of industrial waste, in particular ash and slag waste, creates a number of difficulties.
There are particles, the inner part of which has not melted and is composed of the smallest mineral and coke grains.
Some particles have a spongy surface due to the different number of bubbles.
The coarse ash fractions contain aggregates formed as a result of the sintering of many small grains.
Slag grains larger than 5 mm are present in an insignificant amount (less than 1%).

The grain size of austenite above TA3 plays an important role, which is not captured in this method.
Above TA3 the austenite grains continue to grow.
As austenite grain size increases, the number of ferrite nucleation sites reduces.
Therefore, a large number of CCT diagram is required to capture phase transformations at different positions.
However, this CCT diagram was used for both the fine and coarse grained HAZ regions with different maximum temperatures.

The specimens were then etched with the standard 1.5% nital so as to reveal the ferrite grain boundaries.
The microstructure of AZ61A magnesium alloy at room temperature shows larger grains.
After solution heat treatment, the grains are compactly arranged, without any vacancy of atom and are shown in Fig. 4.
(iii) The microstructure showed larger grains.
Whereas the microstructure of after heat treatment, the grains are compactly arranged, without any vacancy of atom and the hardness was slightly increased.

The alloy is mainly composed of equiaxed grains, and the average grain size of the alloy is about 50 μm.
The solution treated alloy is also mainly composed of equiaxed grains.
From Fig.2, no obvious grain growth occurred when solution treating time increasing.
But grey petal-like specks and twins can be observed in grain interior, and the numbers of them are becoming larger with increasing of the solution treatment time.
From the XRD result presented in Fig.3, a new compound phase Mg41Gd5 was found, which is located grain interior or near grain boundaries as reported in literature [6].

Introduction Thermal barrier coatings (TBCs) are used in a number of energy-related applications [1].
As can be seen, the zirconia grains were irregularly globose and the particle sizes were in the range of 20-70 nm.
Some irregular light grey areas are shown in the images of the zirconia grains.
According to the principle of TEM imaging, the thinner the grains are, the lighter the color is.
The grain sizes are about 0.5 µm.

The pure PZT has an average grain size of ~5 μm.
The average grain size for the 0.5L-0.5N sample was observed to be ~0.9 μm.
The small grain size may also be attributed to the dopant segregation at grain boundaries [7].
The excessive Fe was precipitated at grain boundaries, then the grain growth was inhibited.
The reason for the decreased grain size can be assumed as an inhibition of grain growth due to the segregation of both the donors and acceptors at grain boundaries in this higher concentration of additives.

It can be seen that the shape of alpha particles near grain boundaries is different from that of inside grains.
The precipitates near grain boundaries exhibit the needle structure which can often be seen in metastable beta titanium alloys, while the precipitates inside grains exhibit short sheet structure (Fig.3 (b)) which is very fine and homogeneous.
SEM images of Ti-B20 samples aged at 570℃ for 8 hours after water quenching from 900℃ for 30 minutes(a)near grain boundaries (b)inside grain Grain boundaries usually act as the preferential sites for heterogeneous nucleation, at the same time, they are also effective vacancy sinks.
Though the cooling rate of water quenching is quite high, the vacancies near grain boundaries can still be absorbed, consequently, the concentration of excess vacancies near grain boundaries is relatively lower than that of inside grains.
In despite of the large numbers of vacancies will be absorbed by the phase boundaries, cooling rate can still affect the precipitation during aging treatment.

It may consist of any number of shots.
K1C = f (d) is operational parameter as a dependence function of fracture toughness of carbide material on grain size.
The larger the grain size is, the higher the maximum track width is. 2.
The dependence of the track width from the grain size is more and more obvious with the increasing indentation depth. 3.
The larger the grain size is, the higher the fracture toughness is. 4.

A large number of nuclei are formed on the upper and lower surfaces of the cooling tank.
The number of nuclei increase leads to refinement of microstructure.
The microstructure of semi-solid squeeze casting also is rose grains or fine equiaxed grains.
It can be found that the microstructure consists of rose grains or equiaxed grains under different filling velocity.
The probability of collisions between grains and grains is also greatly increased and the microstructure is relatively fine (Fig.6b).