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When cooling rate is 2~5°C/s, the microstructure is mainly based on granular bainite and ferrite (Fig. 2b, Fig. 2c); as cooling rate rises further, the number of ferrite declines gradually yet bainite increases and lower bainite (LB) appears (Fig. 2d).
When the peak temperature of the second pass of double-pass coarse grain region is 1000°C (higher than Ac3), that is the supercritically reheated coarse grain HAZ (SCGHAZ).
The grains of ICCGHAZ remain coarse as that of primary coarse grain region, which is also one of the reasons leading to decreased toughness [8].
When the peak temperature of the second pass of double-pass coarse grain region is 650°C (lower than Ac1), that is the subcritically reheated coarse grain HAZ (SCCGHAZ).
(3) To avoid forming a large number of martensite due to rapid cooling, and to reduce welding joint cold cracking sensitivity, the weld preheating temperature should be controlled between 100°C and 150°C when X100 pipeline steel is field welding

Fig. 4 shows the relationship between average slip strains and the number of cycles.
In the results of PRI-BSL cyclic with EQ-hardening, activities of both slip systems decrease with increasing the number of cycles (Fig. 4 (a)).
(a) (b) (a) (b) (a) (b) Fig. 4 The relationship between average slip strain and the number of cycles at =0.7 % in the model PRI-BSL cyclic with CRSS ratio of 1:1.1.
If there is any spaces between crystal grains after the deformation, mechanical constraints exist to conform the grain boundary of one grain to that of the other grain.
(a) (b) (c) εyy σyy σyy (a) (b) Grain 1 Grain 2 Grain 1 Grain 2 Fig. 7 Schematic diagrams of deformed shapes of crystal grains when the grains are separated at the grain boundaries.

Fig.1a illustrates the grain size was about 50-200nm.
These structures were not composed of a single grain, but made of several grains.
It is clear that every cellular structure contains a number of fine particles(grains), four grains having strong diffraction contrast are marked as 1, 2, 3, 4 in the figure.
Fig.3a presents one grain morphology in dark field mode.
Who will be dominant is determined by a number of conditions.

It was found that a surface of titanium samples tested on the vibratory stand was covered by very large number of microcracks which in a later stage of the research leads to the erosion of the material.
The average grain size was approximately 20 µm (Fig. 3).
Results of the EBSD evaluation of the Ti99.7 titanium structure: a) the inverse pole figure map, b) the basic triangle, c) the inverse pole figure for ND, d) area fraction distribution of the grain size, e) number fraction distribution of the grain size The Ti99.7 titanium exhibited a good cavitational resistance upon testing on the vibration stand.
In the further step, an effect of uplifting and collapsing of titanium single grains took place leading to a detachment of whole grains or their agglomerates (Fig. 5c-d).
The cavitational destruction of Ti99.7 samples tested at two different stands begins at grain boundaries of the a phase and slowly grows toward an interior of grains leading to a surface damage.

Compared with traditional metal processes, ECAP has a number of advantages such as introducing exceptional high strain without changing the cross section of workpiece.
Annealed at the lower temperature 923 K, the primary α grains were different in size and not well globularized (Fig. 3b).
While annealed at the higher temperature 1073 K (Fig. 3e), the equiaxed α grains showed pronounced growth.
It attributed to the increase in number of grain boundaries, which balanced the decrease in density of dislocations due to annealing softening.
Increasing energy input introduced by longer annealing time led to more complete recovery and recrystallization, and longer annealing time caused grain growth and consequent decrease in number of grain boundaries.

Strain of Grains.
The total number of grains used for the measurement was about 240.
Grain Rotation in Oyz-plane.
Grain rotation is mainly produced by inhomogeneous deformation around a grain.
Fig. 15(a) shows measuring principle of strain inside a grain, where the measuring position is shown with the grain number 2 in Fig. 13.

This image includes qualitatively the crystalline information between polycrystalline grains.
This analysis shows that most grains have the texture of [111] direction normal to films, and a few of grains are oriented in the other directions.
The size of a- or b-axis oriented grains are relatively small, compared to caxis oriented grains, which are imaged in Fig. 1(b) by blue color as indicated by 1, 2, and 3 numbers in Fig. 1(b), and which are also localized in larger area than other grains. θ-2θ x-ray scans were performed to compare the nanoscopic orientations of Fig. 1 with macroscopic polycrystalline orientations (Fig. 3) of BLT films on Pt electrodes.
Ferroelectric domains of c-axis orientated grains, which are indicated by 1, 2, and 3 numbers in Fig. 5(a) and (b), respectively, show no changes in the phase image as shown in Fig. 5(b), even after applied voltage of 10V.
C-axis oriented grains with plate-like morphology show almost linear dielectric behavior.

Results To analyze the grain size of the Samotlor field, the results of grain size distribution for thin sections were used that had been obtained by Nizhnevartovskgaz OJSC specialists and processed at TSGE OJSC by a group of scientists headed by S.B.
The number of wells where studies were undertaken is obviously insufficient for correct the summary interpretation of analysis results.
According to descriptions of thin sections, rocks primarily belong to fine-grained sandstones and large and medium-grained siltites.
In terms of the medium size, as noted above, the sediments under study belong to small-grain sand stones and large and medium-grained siltites, which can be related to low energetic capabilities of the transported medium or to the nature of the distributive province.
A large number of stripes of dynamically related subzones must be checked.

The surface morphology of the films showed more uniform sized grains.
While comparing the MgPc of films, it’s found the intensity of characteristic peak is high as the energy and number of laser pulses increase and the crystallize is monoclinic form is observed in β-form.
Table (2): Shows the grain size (D) that calculated from FE-SEM images.
Table (3): Shows the grain size and surface roughness values for laser pulsed energies (200, 300, 400, 500) (mJ).
FE-SEM analysis showed that the film morphology become homogenously distributes various structural parameters such as grain size ,surface roughness have been estimated ,reported and conclude that as laser pulsed energy increase ,grain size decreases.we also demonstrated that the number of laser shoot pulses play a significant part in the structure of the deposited thin films .

Fig.2 Typical Raman scattering spectra of Zirconia a)Tetragonal Zirconia, b)Transformed Zirconia (tetragonal + monoclinic) a) b) 800 600 400 200 Wave number (cm -1 ) Intensity (a.u.)
a) b) 800 600 400 200 Wave number (cm -1 ) Intensity (a.u.)
Figure 4 shows the measured relationship between grain size and monoclinic fraction after 150 hrs acceleration test.
Grain size ranged only from 0.2 to 0.3 µm.
Phase stability greatly improved with reducing grain size beyond a threshold value.