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A lot of grains are equiaxed grains, and their organization is ferrite, pearlite, and cementite.
A lot of cementite is at the grain boundaries, a small amount of pearlite distributes at the grain boundaries.
Grain sizes of annealed samples are shown in Table 1.
With the temperature increasing, grains turn into equiaxed ones.
（a）850℃{TTP}8451 （b）875℃ （c）925℃ Fig.4 Results of morphology and composition of edult by TEM When the annealing temperature is over 850℃{TTP}8451 , educts increase significantly, the educts are distributing in grain and grain boundary, and a large number of educts are AlN.

XRD, FESEM, SEM and EDS results showed that TiC-TiB2 composites were mainly composed of TiC matrix in which a number of fine TiB2 platelets were embedded, surrounded by the boundary regions consisting of (Cr, Ti) C0.63 carbides.
Recently, Vallauri [2] have successfully prepared the TiC-TiB2-MexOy ceramic composites of fine-grained microstructures by means of pressure-assisted combustion synthesis, and have confirmed the roles of the metal oxides as the promoter of the final product densification and the modificator of the grain refinement.
Furthermore, it was observed by FESEM that a number of fine platelets were embedded in TiC matrix, as shown in Fig. 3.
However, because of higher concentration and faster diffusion of C relative to B in liquid Ti alloy as well as the growth isotropy of TiC, TiC grows far faster than TiB2 does, so that the TiB2 platelets are completely surrounded by TiC grains, as shown in Fig. 3, and the final microstructures that a number of TiB2 platelets are embedded in TiC matrix are achieved.
In addition, FESEM images of the crack propagation paths demonstrated that as the crack is met by the large TiC grains, the crack propagates along the grain boundaries, and crack-bridging by TiC grains is initiated due to crack-branching effect, as shown by the arrow A in Fig. 5(b), subsequently, as the crack is met by the fine, hard TiB2 platelets, the crack is often arrested due to crack-pinning by the fine, hard TiB2 platelets, as shown by the arrow B in Fig. 5(b).

In contrast to most grains, the EBSD map from the grain at the crack tip, Figure 4, distinctly shows the presence of lattice rotation ahead of the crack.
The grain deforms significantly where the crack enters the grain and the orientation rotates by about 5º from the original orientation.
Such a spread in orientation is also observed in grain 8.
Acknowledgements The author would like to acknowledge the EPSRC, Grant number EP/H022309/1, EP/H500375/1 and Rolls-Royce plc. under the TSB project ’Siloet’ TP NUMBER: AB266C/4 for funding and the Prof Lindsay Greer of the Department of Materials Science and Metallurgy, University of Cambridge for provision of facilities.
Energy of slip transmission and nucleation at grain boundaries.

Nucleation at boundary Twinning Recrystallization at prior grain boundary Recrystallization associated with particles Nucleation associated with second phase particles 50 µm 30 µm 30 µm Journal Title and Volume Number (to be inserted by the publisher) Fig. 3 Dynamic recrystallization and twinning in Alloy A1 extruded at 573 K Experimental Alloy A1 Summary.
Many of those new grains were associated with grain boundary particles.
Fig. 7a Nucleation of new grains in WE43 extruded at 633 K New grains beginning to nucleate dynamically in shear band Evidence of dynamic recrystallization at preexisting grain boundary Build up of subgrain boundary around particle Shearing of grain during deformation Recrystallization associated with particles along pre-existing grain boundary Recrystallization associated with particles Nucleation at grain boundary Nucleation at particles Fine particles that precipitated out during extrusion 25 µm 8 µm 10 µm 12 µm Journal Title and Volume Number (to be inserted by the publisher) The microstructure of WE43 extruded at 663 K is shown in the EBSD map in Fig 7b and it is possible to identify new grains recrystallizing.
New grains also nucleated at grain boundaries and those new grains were often associated with grain boundary particles.
New grains were observed nucleating at particles within the matrix and at grain boundaries.

Although surface hardness of SFAP is decreasing with grain size number increasing, surface hardness of SFAP in different grain size is no evident distinction.
While in the same 65 wt% abrasive weight percent, Young's modulus of SFAP is decreasing with grain size number increasing, as Fig.8 shows.
Under the same load, it causes the number of the surface grains of SFAP increases escaping from SFAP.
And with the same abrasive weight percent, shear strength of SFAP is decreasing along with grain size number increasing.
Under the same abrasive weight percent, Young's modulus of SFAP is decreasing with grain size number increasing. 2.

The β platelets which were aligned between the recrystallized α grain and the recovered α grain were responsible for the microcrack generation to form (0001) tansgranular facet in the recrystallized α grains.
The microstructure is classified into two regions, which are designated as recrystallized a grain region and recovered a grain region as shown in Fig. 2.[8] The recovered a grains showed a strong texture with (0001)<1120> rotated counterclockwise about 25 degrees around RD (rolling direction) where the highest pole density was about 50 (Fig. 2(b)), while the (0001) of recrystallized a grains were (0001)//ND (normal direction) plane (Fig. 2(c)).
A number of microcracks or voids generated at β platelets in the recovered a grain region, and the origin of (0001) transgraular microcrackings in α grain was usually associated with the β microcracks as shown in Fig. 3(a).[8] That is why the recovered α grains and β platelets behave as ‘softer’ region than the recrystallized α grains under cyclic deformation at very low stress level.[2,12] The traces of the α microcracks shown in Fig. 3(b) were on (0001), which appeared on the microcracking part in the crack initiation site.
In the step (1), the {1010}<1120> slip predominantly operates and developes fairly planar dislocation arrays in the recovered a grains.[11] Slip deformation analysis based on full constraints model by Taylor theory was suggested that internal stress in a grain was developed on the normal to (0001) and hardly relaxed.[13] Since the arrays are piled-up at the boundaries between recrystallized a grain region and recovered a grain region, the accumulated tensile stress along [0001] may develop a local stress concentration in the neigboring recrystallized a grain.
At first microcrack or void was generated in β platelet between the recovered α grain and the recrystallized α grain.

The concentration stress is related to the number of dislocations and the length of slip bands in dislocation accumulation group, so the fracture stress and crystal grain size have the following relation: 2/1 0 − += dkgg σσ (1) σ0 is intergranular fracture force, and kg is a constant that is related to the binding energy among the grain boundaries, d is the diameter of grain.
According to the formula, the smaller grain size, the greater fracture stress along the grain and the greater the intensity [4].
The smaller the grain size, the more the grain boundary and the greater the energy consumed by plastic deformation, which is the main portion of the crack propagation resistance.
In the samples, there was occasionally a small number of glass phase among the high melting point crystals (Figure 6(c)), and in most cases, the grain boundaries were very clean (Figure 6(d)), which indicated that there was little glass phase in the samples, and the grains were combined with each other most directly, which would improved the condition of the grains boundary, furthermore increased strength and toughness of materials [4].
The distribution probability of nano- aperture was the largest, and the volume of micron- aperture was the maximum, but all pores were less than 4µm in diameter; (4) Grains of the samples were fine, mostly below 2µm; there were little glass phase among grains, which lead to enhance of direct combination among grains; the samples had micro pore structure.

But various research interests of access contral are still faced with quite a number of challenges.
As to achieve those requirements, we introduce a fine-grained access contral technology (FGAC) for the data-centric business process model.
This paper will briefly introduce the access rights and propose a fine-grained resolution mechanism in data-centric business process model.
Fine-grained access control model Windows and views give a rather coarse grained mechanism for specifying the access rights of participants to the contents of artifacts.
[2] Jie Shi, Hong Zhu: A fine-grained access control model for relational databases.

Introduction The grinding process is composed of the instant and high-speed motion, which is done by a large number of tiny abrasive grain edges, and the process has the character of complexity, randomicity and unemersion.
When the abrasive grain size is definite, the grain radius is within a certain range.
A specific grain radius is in the following range: )fk(1dd did 0i += (1) Where di is the radius of grain i(mm); d0 is the average radius of a certain grain size (mm); kd is the change coefficient of the grain radius and fdi is a random number equably distributed in [-0.5, 0.5] engendered by the computer.
Supposing that the grain is a rough geometry object which approximates a sphere, the grain contour line height in the section which is the cross-sphere center and vertical to the grain movement direction [4] is given by： ( ) (x)]fk(x)f[kd)x(x/2)(dzxz rir sisi 2 i 2 i i + +−−+= (2) where xi, zi are the grain sphere center position coordinates (mm); ks, kr are the grain geometric shape coefficient and grain roughness coefficient, respectively and fsi(x), fri(x) are the grain geometric shape function and grain roughness function, respectively, their value being different on the each point of contour line, and a random number equably distributed in [-0.5, 0.5].
The surface roughness has relationship with the grain number of the identity area, the grain distribution, the cutting trail and so on.

The material flow/deformation characteristics as well as the degree of grain refinement, as a function of different initial grain morphological orientation, vis-sa-vis grain orientation, are studied.
A number of individual optical microscope images were collected throughout a sample from transverse pane of each orientation billets after etched with Krolls reagent (2% HF, 6% HNO3 with distilled water).For TEM observation, samples were sectioned from theflow plane (y-plane) in all orientations billets using a slow speed diamond saw to obtain slices of thickness less than 400 µm.
The microstructure consists of bigger equi-axed grains in the size range 100-200µm with fine equi-axed sub-grains in the range 5-10µm in size.
Within these elongated grains fine, more or less equi-axed grains are observed.
A strong grain to grain interaction leads to strain hardening for substantial changes in end orientation.