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Przylenk [5] claimed that material removal had some relation with the number of grains contacting with workpiece surface.
Jain [12] has studied the effects of different process parameters (number of cycles, abrasive concentration, grain size) on material removal and surface finish based on experiments.
Meantime, the active grain would slow down, and others grains around which would squeeze the active grain as shown in Fig 1(c).
Fig.6 Two types of arrangement of grain in fluid abrasive Grain squeezing forces.
The distribution state of grains could be the following two types of arrangement, as shown in Fig.6.The number of all grains could be estimated by the following equation, Where, R and L are radius and length of workpiece. r is grain size.

A linear relationship between the area fraction of DRX and the number fraction of Σ3 boundaries was observed during hot deformation.
It is observed that like Σ3 boundaries, a linear relationship is exists between area fraction of DRX grains and number fraction of Σ9 boundaries.
For example, the number fraction of S3 boundaries increases from 0.45 in the SA condition to 0.58 in the specimen shown in Fig. 2, while the number fraction of S9 and S27 boundaries increases from 0.029 and 0.008, respectively, in SA condition to 0.078 and 0.041, respectively, in the same specimen.
These large numbers of S3-S3-S9 and S3-S9-S27 triple junctions, in turn, fragments the connectivity of random HABs in the GBE microstructure.
A linear relationship between the area fraction of DRX grains and the number fraction of Σ3 boundaries is observed during hot deformation.

Due to the grain itself is a living organism, constantly engage in life and biochemistry movement, so as to consume the nutrients of grain particles in the process of grain storage; and at the same time, insects, mold, mice and sparrow in the grain bulk ecosystems also will do harmful it and cause the food reduction in the storage.
There has great significance to guarantee food security of the country by improving the level of grain storage, combining advanced computer technology with grain storage work and designing and developing appropriate expert system of grain storage.
This system can warn some factors which are not conducive to grain storage, help to improve the maintenance efficiency and management level of grain storage and reduce the loss of the grain in storage process.
Figure2 The flow chart of inference mechanism In inference process , the system matches the currently known facts with knowledge in the knowledge base constantly, at the same time a prerequisite of a number of knowledge may be satisfied that the knowledge are matched successfully and form the conflict.
Grain Processing. 2011,36(1): 70-73

So the austenite grains grew sharply and some grains were abnormally coarse, and the grain size was not uniform.
And with the increase of temperature, the number of lath martensite increased gradually, and the size of lath martensite also increased.
With the increased of heating temperature, the number of carbides decreased obviously.
Therefore, the number of lath martensites increases gradually.
According to the analysis, when the heating temperature was 790 °C, the ferrite content in the quenched structure was higher, and there was a large number of undissolved carbides, so the hardness and strength were relatively low.

After ARB processing an ultrafine-grained microstructure is obtained.
The stacking order with increasing number of ARB cycles N can be seen in Table 1.
Structure of AA6014/AA5754 laminates with increasing number of ARB cycles N.
The evolution of the grain structure with increasing number of ARB cycles is shown in Figure 3.
The grains of the AA5754 layers are finer than the grains in AA6014.

The objective of this work is to study the effect of cross section of the billet, number of passes on grain refinement, mechanical properties and wear behaviour of AA 5083.
It is observed that the wear rate and coefficient of friction are reduced with number of passes in both the cases and rate of decrease is more in case of square billets. 1.
This process has great impact for developing ultra-fine grain structure consisting of equiaxed and homogeneous grains with high angle grain boundaries[6-13].
In addition to the grain refinement, the porosity and blow holes are reduced during ECAE of square billets and more homogeneous grain structure produced.
· The wear resistance of the raw material is low and is increased with increasing number of ECAP passes for square and circular billets.

The total number of particles per unit volume decreases in the order of Zr > Mg > Ce > Ti.
It is seen that the mean grain size decreases with increasing the number of inclusion particles.
It is seen that the effect of soluble Zr and Ce on inhibition of austenite grain growth 0 min at 1200 Co N / mmV-3 0.1 1.0 60 min at 1200 Co Fig. 3 @Relation between number of @ @ @particles, NV, and mean size @ @ @of grains, DA.
The effect of nonrandom dispersion of particles on austenite grain growth was estimated by using the fraction of oxide particles on grain boundaries, ΦA, which is defined as the ratio of the number for particles at the grain boundaries and the total number of particles per unit area.
Summary In Fe-10% Ni and Fe-0.05% C alloys deoxidized with Mn-Si, Ti and Mg, the austenite grain size can be controlled only by the number and size of inclusion particles.

Introduction The grain size of a metal has a large effect on its properties, and the refinement of the grain size has many technological benefits.
Recently, the product of ultrafine-grained structure with a grain size of about 1µm or lower in various steels has been actively studied.
One is that a heavy deformation is applied to the matrix phase before transformation in order to introduce a large number of nucleation sites for transformed product.
Recrystallized γ grains are pinned by finely dispersed α particles and then maintain fine grain size (1～2µm).
On the other hand, most of α grains are subgrains surrounded by low-angle boundaries in the fine-grain region as shown in (e).

The grains grows up and some grains are still intergranular crack for the samples annealed at 810 ℃.
The numbers of the intergranular crack grains decrease and the cleavage planes increase for the sample annealed for 180sec at 840℃.
As seen, there is apparent phosphorus segregated at grain boundary.
The main reason is that Ti-IF steel is cold-rolled by 75% reduction and a large number of vacancies and dislocations are introduced in the matrix.
The grains grow up and the intergranular crack grains decrease for the sample annealed for 180sec at 840oC.

However, the microstructure evolution during HPT has been examined in details for restricted number of pure metals and alloys [1-3].
The numbers indicate the misorientation in degrees.
Second, the boundaries of some grains acquire an ability to migrate; new grains involving annealing twins and low dislocation density consume grains with size less than 100 nm that contain high density of lattice and grain boundary dislocations.
Fig. 5. a- Effect of strain on microhardness and recrystallized grain size after annealing at 500°C, 1 h of a Ni-20%Cr alloy. b - Schematic drawing for variation of structural mechanisms responsible for new grain development during annealing of cold-worked Ni-20%Cr alloy, where Nn – number of recrystallizing nuclei, Ns – number of strain-induced grains/subgrains.
In contrast, at lower strains, the number of nanoscale grains evolved is very restricted.