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The coil is made from enameled wires with a diameter of 0.49 mm and the coil turns number is 1100.
It is found that the grains in fusion zone are much finer than those in heat-affected zone and base metal.
The growing direction of most weld grains deviated from the welding center, shown in Fig.9d and Fig.9e, is toward a certain direction.
When the exciting voltage is 20 V, the grain size is finest.
The grain size with AC magnetic field is much finer than that obtained with DC magnetic field.

Number and height of protrusions per unit surface grew with time, temperature and increasing hydrostatic pressure.
Diffusion flux is directed to a stress-free grain from surrounding stressed grains and the stress gradient at the boundary of the stress-free grain is of order of σ / Rw.
A hemispherical Cd grain of radius Rg is under compressive stresses.
Whisker growth model: hemispherical Cd grain is located on the surface; inside the grain there is a segment of edge dislocation between two screw dislocations of opposite signs.
Using Eq. 9 we can estimate compressive stresses in the grains surrounding the stress-free grain where the whisker grows.

However, much crystal grain scatters on the ground surface of sample C and D (Fig.C and Fig.D), the mean grain size is about 0.35µm, which approaches to the mean grain size of the samples.
Grain boundary cracking and crystal grain dropout are main removing method.
This is probably because there are many flaws introduced during the sintering procedure on the grain boundaries.
The flaking and brittle fracture is the main removing method for the samples with high flexural strength, and grain boundary cracking and crystal grain dropout are the key removing method for the samples with low flexural strength.
Large numbers of cracks would easily propagate and breach the ceramics which were subjected to enough high shear force such as grinding force.

For this purpose a number of specimens are placed inside the RPV for exposure to the neutron irradiation in the real environment.
These variables are; Flux (Φ), the amount of radiant energy (number of neutrons per second) passing through a unit area, Fluence (Φt), the number of particles delivered per unit area and Irradiation temperature (Ti) [5,6].
Irradiation induced/enhanced grain boundary segregation of embrittling elements such as Phosphorus.
Its damaging effect is either in segregation on grain boundaries with subsequent intergranular fractures or precipitates with other solute atoms inside grains [9,10,11].
Flewitt, Combined quenching and tempering induced phosphorus segregation to grain boundaries in 2.25Cr-1Mo steel.

The average grain size decreased when addition with LCMO were increased.
The grains gaps, porosity, and grain size decrease when the weight percentage of LCMO increases.
The average grain size for pure YBCO is 20.63μm, addition with 0.2 wt% is 17.90 μm, addition with 0.4 wt% is 16.59 μm, and addition 0.6 wt% is 14.88 μm.
SEM morphology (a) pure YBCO, (b) addition 0.2 wt% of LCMO, (c) addition 0.4 wt% of LCMO, and (d) addition 0.6 wt% of LCMO Conclusion The effect of addition La0.67Ca0.33MnO3 in YBCO system increases the number of peaks, increasing the intensity of peak, and formed new phases.
The average grain size, gaps, and porosity decrease due to the increasing addition weight percentage of LCMO.

The effects of deformation temperature T and strain rate can be combined as the number of thermally activated events per unit strain, which can be expressed in the Zener–Hollomon parameter, Z, as shown in Eq. 1
At 730°C the elongated grains and the thick grain boundaries were observed, as shown in Fig. 5 (d)(e) and (f).
The previous study has indicated that boron in the form of Fe2B segregates along the grain boundaries in the Fe-Ga alloys, leading to the thick grain boundaries.
For the sample tested at 900°C with strain rate of 0.1s-1, inset within the scan is a close-up of the local, a large number of sub-grains in the grains is observed (Fig 5 (g)), which demonstrates that the dynamic recovery occurred under this deformation condition.
At 900°C fine DRX grains are observed along some grain at higher strain rate (1.0 and 10 s-1), as shown in Fig.5 (h) and (i).

The crystal structure and grain size of the particles were determined, using X-ray diffraction (XRD).
Copper oxide (CuO) is considered a material as a capacitive type gas sensor for sensing, and also it can detect a large number of gases [7].
Dielectric behavior can effectively be used to study the electrical properties of the grain boundaries.
There is no difference in the electrical properties of the polycrystalline CuO with same grain size.
In nanophase materials, the grain boundaries have an amorphous or glassy structure.

The SEM results showed the average particle size (84-214 nm) and the average grain size (0.35-2.09 µm) of samples increased with the increase of firing temperatures.
The diffraction synthesis lines were indexed on the basis of a orthorhombic structure matched with a JCPDS file number 10-0268.
The average grain size of SrZrO3 ceramics increased from 0.35 to 2.09 µm when the sintering temperatures were increased from 1400 to 1650 oC.
At 1550 oC, the average grain sizes increased from 1.36 to 2.63 µm when the soak time was increased from 2 to 8 h.
The average particle size and the average grain size increased with the increasing of calcination and sintering temperatures.

In regions without cracks, grain size was normal and the ferrite was fine and distributed uniformly within the grains.
Such large grain size is much greater than the fine grain size of new solid forming on the mold wall.
In fact, Dippenaar has recently proposed that austenite grain size is influenced by the grain size of pre-existing delta ferrite, which puts blown grain formation at, or just behind the solidification front [6].
The average grain size was 1220±600 microns.
In reality, because of the nucleation barrier for the precipitation, the actual precipitation temperature will be lower and a sudden explosion in number of the precipitates is expected at lower temperature due to a high super saturation condition.

The crack propagation is along prior-austenite grain boundaries and is affected by MnS inclusions.
Thus, the crack propagation is along the prior-austenite grain boundaries.
The ferrite, some of which has widmanstatten characteristic, proceeds along the prior-austenite grain boundaries.
Thus, prior-austenite grains in 0# position is coarsening.
MnS inclusions at cross-section of sample 45#, the number of which is less than that of sample 0#, are distributed approximately parallel to the surface as showing in Fig.7 (b).