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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).

In multipass welded joints, the unfavourable microstructural changes of both abovementioned zones (grain growth and brittle microstructure at grain boundaries) can occur in the intercritically reheated coarse-grained zone, which is supposed to be the region of the whole welded joint with the lowest toughness [1].
The Gleeble thermomechanical simulator offers considerable flexibility both in thermal cycles and loads that can be applied to a number of different sample geometries.
In order to simulate HAZ areas with lowest toughness, the chosen parts of the HAZ were the coarse-grained (CGHAZ), intercritical (ICHAZ) and intercritically reheated coarse-grained (ICCGHAZ) zones.
Coarse-grained heat affected zone (CGHAZ) thermal cycles Fig. 3.
The M-A constituents at the boundaries of the grains cause local brittle zones.

Singh reported that UV and VUV Photons in lights from tungsten halogen lamps provide a large number of electronic excited states to participate in the photo thermal process [1].
The grain size is biggest crystallized at 850°C.
The experiment show there exists discrete quantum states in the connection between the grain size and the temperature as the experiment.
The transitions between quantum states with different quantum numbers should forced by the certain energies corresponding to the proper temperatures.
Conclusion Amorphous prepared by PECVD on glasses annealed by rapid thermal annealing method, respectively, it is found that (1) There existed discrete quantum states in the connection between the grain size, the grain size is biggest at the 850°C temperature. (2) The thin film made by pulsed rapid thermal method is smoothly and perfect structure.

The SrTiO3 crystal grains size was 0.50 ´ 0.15 μm.
But there were some cracks between the grains.
The number of the generated Sr[TiF6-n(OH)n] or Sr[TiF6-nOm/2(OH)n-m] crystal nucleus was larger.
There were 0.10 ´ 0.40 μm pores between the grains.
The grains didn’t cover the whole substrate totally.

Scanning electron microscopy analysis of sandstone shows when magnified 1000 times there are visible microcracks about 10~50 μm; when magnified 2500 times there can be observed microcracks and grain dissolution hole.
Can be seen from the above analysis, B10 coal’s microcracks are more developed and has good connectivity, wide crack, and particle surface erosion is serious, and there are a large number of dissolution holes.
They have good connectivity and filling with strongly swelling sheet I/S mixed layer mineral among grains.
Compared with coal and sandstone, the microscopic structure of mudstone is relatively better, the number of microcracks and pores is relatively few, and the width of the crack is smaller.
Microcracks and pores are developed and have good connectivity and grain table is seriously corrosion

Table 1 Serial number and compositions of the SnO2 samples Sample No.
With 0.1 mol% Sb2O3 doped in the SnO2+0.5%CuO ceramic, the grain size undergoes a fast growing during the sintering process (Fig.2b): the high grain boundary mobility entraps small-diameter pores within the grains and at grain boundary.
However, when Sb2O3 increases to 0.5 mol%, the grain size is smaller and the relative density is higher (Fig.2c and Fig.1).
When the amount of Sb2O3 reaches 1.0 mol%, a large number of through pores are found at grain boundary (Fig.2d).

workpiece small abrasive grains big abrasive grainsLoad plastic agent semi bonded abrasive plate weight workpiece Fig.1 "Slump" mechanism of semi bonded abrasive plate Fig.2 Schematic diagram of Semi bonded abrasive lapping system In order to improve surface quality of Ge substrate efficiently, one effective strategy is increasing the number of active grains while maintaining processing load, which results in reduction of grits grinding force.
Semi bonded abrasive plate is manufactured of plastic agent, additive and abrasive grains.
Because of plastic agent, the big protruding abrasive grains will slump into plastic agent in processing, as it is shown in Fig.1.
The number of active grains will increase and the grain depth of cut will decrease.

With the calcium ion’s doping into the crystal lattice of zirconia, the vacuum of oxide appears, which can conbine with zircium easily, and the number of hydroxo groups decreased, so the precursor of CaO stablized zirconia powders is ZrO2·nH2O.
So the oxygen vacancy which is combined with Zr4+ ion increases, while the coordination number of Zr4+ ion decreases, which leads to coordination number is lower than 8 and the ZrO2 powers maintain cubic phase.
The growing rate of grains are related to the difference between the adjacent grains on two sides of interface [12], the greater the difference between adjacent grains, the more favorable for boundary migration and the faster the grains grow.
Under 1100℃, CaO stabilized ZrO2 powders is nearly cubic, the structural features of the grains is similar and the interface energy is low, so the grains grow slowly and the grains size is small.

As the alloy homogenized by 455°C/16h, except for needle-like phases inside grains, part of phases on grain boundaries had dissolved into the matrix and exhibited rounded shapes.
Except for eutectic phase on grain boundaries, a large number of needle-like phases in the matrix distribute along grain boundary.
The needle-like phases in the matrix almost dissolve into the matrix completely and only few of them next to grain boundaries remain.
In the as-cast microstrure, the area fraction of second phase on grain boundary possesses a proportion of 3.28%.
The as-cast alloy contained needlelike Al2CuLi and Al2Cu phase in the matrix and Cu-rich phase and Ag-containing phase on grain boundary.

The number of WEC and thickness of each WEC increases as the test temperature increases.
In the dark field image (b), some fine grains are found here as indicated by the arrows.
The diffraction pattern also shows the existence of crystal grains with different crystallographic orientations.
These photographs indicate the existence of many ultra fine grains with different crystallographic orientations in the area of WEC.
The diffraction pattern demonstrates a random distribution of these ultra fine grains.