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Precipitates can be seen in the grain boundaries and polycrystalline grains.
Fig. 3b is the magnified image of Fig. 3a, focusing on the crystalline precipitates in grain boundaries (index B) and polycrystalline grains (index C).
The precipitate E in the grain boundary shows a bright contrast compared to the matrix D.
Al- and Ni-rich precipitates were embedded in the grain boundary region in the fine-grained polycrystalline structure in melt-spun ribbons.
Acknowledgements A part of this work was supported by JSPS KAKENHI Grant Number 15K06484 and by scientific grants from the Japan Foundry Engineering Society (JFS).

It has been found that the grain size decreases with the increase in Na0.5Bi0.5TiO3 content.
This retards the mass transport and, as a result, smaller grains are formed [D[] C.
As is known, the total number of insulating grain boundaries increases with decrease in the grain size of PTCR ceramics.
During the reoxidation process, oxygen diffused from the grain boundary toward the center of the grains.
The grain size decreased with the increase in x.

Introduction The siliconized layer has attracted attention in the field of engineering because such structure has a considerable number of practical applications and fundamentally interesting properties [1,2].
It could be seen from Fig.2 that the size of the grain and the amount of space among grains were relatively coarse and large when the frequency was bigger or smaller (Fig. 2 a, d, e).
There was a relatively flat finer grain structure at 1000Hz (Fig. 2 b).
The smaller on-time resulted in less crystal nucleus and coarse grain.
While the frequency was lower, the agglomeration of nucleus caused increase of the grain size.

a c b A A A t t t Journal Title and Volume Number (to be inserted by the publisher) 203 In the process of ultrasonic vibration machining, the diamond grains in the working fluid shock the PCD surface periodically.
The number of these micro-cracks and their size are lie on the number of thermal impact and the temperature gradient.
Therefore, the blunted or defective diamond grains crash and the loose grains drop down, which makes the distribution of diamond grains more suitable.
The loose grains certainly drop down in the grinding process.
Journal Title and Volume Number (to be inserted by the publisher) 205 2.

The quasicrystal particles distributed in the grain and grain boundary.
The average grain size is about 55µm.
The average grain size is 25µm.
When the addition level reaches 15%, the average grain size is 10µm.
The coarse and developed dendrites in matrix alloy were transformed into small equiaxed grains, and the grains were refined effectively.

The average grain size was about 200 μm.
The number of recrystallized grain in samples heat treated under 12T high magnetic field is more than that in samples heat treated without 12T high magnetic field, but the size of recrystallized grain is similar in samples heat treated at same condition with or without 12T high magnetic field.
The number of recrystallized grains increases significantly in samples for eight cryoECAP passes, but the size of them changes little with prolonging annealing time.
The fibers entirely disappear, the number of recrystallized grains increases while the size of the recrystallized grain change little. 2.
Comparing with sample treated without high magnetic field, The distorted level is lower, the fiber is weaker, the number of recrystalllized grain are more, the size of crystallized grain is same in samples treated at 12T high magnetic field.

Equiaxed grains containing Al-Fe, Al-Fe-(Mo, V), and Al-Zr phase particles were characterized.
Apparently, the equiaxed grain structures and finely distributed dispersoids within grains and at grain boundaries are observed in all specimens.
Therefore, a considerable number of dispersoids would be formed through a precipitation reaction from the Al matrix during subsequent hot working.
The decrease in hardness seems to be ascribed to the growth of dispersoids and grain size.
Equiaxed grain structures and extremely fine dispersoids were observed and a finer microstructure both in terms of grain size and particle size could be obtained in the ME specimen.

With the increasing of normalizing temperature,the grain grows,the impact property is decreased.
Just from the perspective of grain size scale,the average grain size scale of normalizing sample C at 910℃ ranks first,but the grain size scale of dark brown pearlite is lower than normalizing sample B,C respectively at870℃ and 950℃, that is to say,the grain of pearlite is coarser than the other two normalizing samples.
Though the average grain size scale of normalizing sample B at 850℃ ranks is lowest,its average grain size of pearlite is higher than other normalizing samples.
Therefore,at the range of 850℃～910℃, the average grain size scale of tested EH36 ship plate steel augments with the increasing of normalizing temperature,i.e.the grain gets smaller gradually,but the average grain size scale of pearlite shows a decreasing tendency,i.e.the size of grain gets more and more bigger.
The reason may be that,though there was more pearlite included in the microstructure at 910℃,the average grain size of the pearlite was lower than sample B’s,that is to say,the average grain size of the pearlite was considerably larger,while at 950℃ the average grain size scale of sample D was higher than sample C,and in general,its average grain size scale was not far from sample C’s,the grain was relatively fine and homogeneous,so its hardness was higher than that of sample B,C at 910℃,870℃.

Then, with )(k T denoting the Cauchy stress in kth crystal, these assumptions lead to [3]: ∑= − = � k k T � T 1 )(1 (8) where −T is the volume averaged stress, and � is the total number of grains comprising the material point.
So each grain is modeled to allow for non-uniform deformation between the grains and within the grains, and both equilibrium and compatibility are satisfied in the weak finite element sense.
In this study, we varied the number of elements and the number of grains in each element, and the distributions of grain orientations in mesh.
On the contrary, the finite element polycrystal model takes each element as a grain, non-uniform deformation between the grains and within the grains can be remained, and the deformation of this polycrystal model is continuous and coordinated.
Due to the friction and limitation of assumption and number of elements, the surface roughness curve from the experimental results show a much higher frequency fluctuation than those of the models.

In most of the observed cases, the growth of the recrystallized grains led to nearly homogeneous equiaxed grains of a similar size.
The microstructure and the texture evolutions in the deformed and the recrystallized states were mostly investigated by TEM, including TEM-based orientation mapping in a number of samples deformed up to 7 passes.
The amount of grains in the ultrafine range increased, but the further (>2 passes) grain refinement was significantly slower.
At later annealing stages, the large grains resulting from the intense grain growth were observed mostly in the places far from the large SPPs.
The size of the new grains was only occasionally greater than the average grain size, and their shape was nearly equiaxed.