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Thus it is necessary to make grains of AZ80 alloy as fine as possible [4, 5].
So sub-micron even nanometer microstructure will be gained, and the strength and plastics will be improved greatly with fine grains.
The study of the applying of ECAP method on grain refinement by acquiring great plastic deformation was widely investigated [6-8].
Automatic mesh and element for workpiece were generated by the soft, and the number of node, element and polygon on surface were 1256, 8000 and 1562, respectively.
So the sizes of grains of the sample are not equivalent because stress and strain distribution of its cross section are not uniform, Therefore, large angle mould is suggested to adopt priorly for the material with high deformation resistance to accumulate large strain by adding the pressing pass number.

Averaged values were reported as hardness numbers for the specific sample.
The microstructure is inherently dendritic coarse-grained in the weld zone before heat treatment and composed of ferrite and pearlite phases.
Water quenching followed by tempering generates tempered martensite, resulting in tough and hard properties with fine grain size.
At higher temperatures, the number of ductile phase fractions will increase, followed by an increase in the size of the carbide particles.
Strength and hardness at each tempering stage are related to the interparticle space, grain size, particle size and distribution, and dislocation density.

Ultra-fine grained and high hardened Al sheet was obtained by Equal Channel Angular Pressing (ECAP).
Then these plates were annealed at 550 ° C for 2 hours to homogenize the initial grain size through thickness (named initial Al sheet).
The grain of initial Al sheet exhibited an equi-axial, uniform, and coarse structure.
The grains were elongated, having an angle of 15-30 degrees to the pressed out direction.
The degree of shear plastic deformation increases with the increasing the number of ECAP passes and was also related to the increase in hardness

The moving of high-angle grain boundaries is blocked by minor precipitations and also the growing of nuclei over recrystallization [6].
The number and the size of precipitations at 490°C is smaller than at 610°C where precipitations can be found in bigger size and number (Fig. 1.).
Either precipitation may operate as nucleation forming places or they can slow down the moving of grain boundaries during recrystallization.
Fonseca: Grain Boundary Area, Grain Boundary Curvature and Particle Pinning in an Al-1mass%Mn Alloy Containing Al6Mn Precipitates, Materials Science Forum 467-470 (2004) 991-996
MOULD: Recrystallization and Grain Growth in Metals, Surrey University Press, London, 1982.

When the crushed run rock functioned as subcrust, the biggest grain size of gravel shall not be more than 37.5 mm. if the grain size is too big, it is easy to segregate and to the disadvantage of blending, mechanical spreading, rolling and leveling.
Its maximum dry density is 2.36 g/cm3 and the best water content is 3.8%.The specific numbers can be seen in the following FIG. (2).
(4) applying a roller to roll in the way of static pressure a time after coarsely leveling, and accurately hanging line by every 10 metres, Fine flat should scraped from roadbed to center with the ground machine, while some low-lying places apply with artificial material filling, last fine flat again; According to the actual experience of the project , trying to reduce the number of fine flat, the occurrence of segregation phenomenon can bereduced.
If adopting the cross job, the uniline must be must overlapped with the width of 1/2 wheel, which is in favor of the stable and close-grained skeleton structure.
(2) The maximum grain diameter of crushed run rock subcrust should be strictly controlled with heavy compaction test to determine the optimal water content and the maximum dry density

In fig. 1 the cut-off points of samples in the valve plate are shown and marked with numbers 1, 2, 3.
High-temperature deformation leads to the jagged structure of the austenite grain boundaries, which is inherited by the low-temperature structure [11, 12].
In the sample from point B, small-sized equiaxed grains (6–9 μm) are noted, and the grain boundaries jaggedness almost disappeared as a result of recrystallization.
In the course of further polishing of the micro-slice, a crack arises, which spread from the shrink-hole along the grain boundaries with the transition to the base metal (Fig.2, b).
The crack in the surfacing and steel spreads along the grain boundary, where particles of non-metallic inclusions are often located, which facilitate its movement.

The SEM image of b-HAp showed plate-like grains 0.3-0.5μm in size (Fig.1) .
By adding partially dissolution treatment, many of the grains became smaller and spherical [7].
The structure of fg-HAp ceramics, forming gradations in both the crystallinity and the grain size of HAp, may make body fluid permeate the parts of the living body where the fg-HAp is used because of graded micropores with nano-order and microcracks of grains.
Flat and plate-like grains 0.3-0.5μm in size.
Fig.5 SEM photograph of the fg-HAp•SBF Ratio of bone and carrier implanted materials (values are given as numbers of implants containing bone/total numbers of implanted materials).

The crack ends meet many grain boundaries on a finer bainite structure, so the direction of the crack changes continuously.
The strength of steel will increase with the increasing number of carbide particles dispersed in the ferrite phase.
The crack propagates slower at below 55,000 cycles and then speeds up as the number of cycles increases.
The number of cycles plotted in Fig. 3a is from 51,000 to 92,000 cycles.
It is known that the direction of the crack will follow the next grain boundaries.

From Fig 5(c), coarsened grains and precipitates are observed at the TMAZ and more severely coarsened grain at HAZ.
An uni-axed grains are noticed in UMR shown in Fig. 6(c).
A large than that equi-axed grains were spot at HAZ shown in Fig. 6(e).
The grain size of 6061 Al matrix was refined after FSP.
The obtained hardness values are much higher than the hardness of the as-received Al due to severe grain size reduction and also the presence of higher number of Al2O3 reinforcement particles in the SZ.

Compared with Silage corn stalks group , sweet sorghum straw bio-feed fermented by the Compound Microbial Agent could also improve the content of milk protein (14.03%,16.81%)and butterfat rate (16.3%, 92.98%) and reduce the somatic cell's number(5.15%,6.86%) in the milk.
The experimental results indicated that the content of milk protein and butterfat rate in fresh milk produced in the trial period has respectively increased 14.03% and 16.3% respectively, while the number of the somatic cell has reduced 5.15% compared with control group (Table3).
While the number of somatic cell in the three above periods have reduced 1.39%,6.86% and 6.07% separately compared with control period (Fig3).
Compared with control group * P＜0.05, ** P＜0.01; Fig1 Variation of milk protein content of milk samples Compared with control group * P＜0.05, ** P＜0.01; Fig2 Variation of the butterfat rate's content of experimental group and the control group Compared with control group * P＜0.05, ** P＜0.01; Fig3 Variation of the somatic cell's number of experimental group and control group Discussion In this work, the test results indicated that the sweet sorghum straw bio-feed fermented in bags and cellar pits by the Compound Microbial Agent both could increase the content of the crude protein and reduce the content of fibrinogen, which could also improve the content of milk protein and butterfat rate and reduce the somatic cell's number in the milk.
Passoth.Effect of starter culture inoculation on feed hygiene and microbial population development in fermented pig feed composed of a cereal grain mix with wet wheat distillers’ grain[J].Journal of Applied Microbiology. 108(1): 129–138