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At this time, the number of wearied and newly presented cutting edges arrives at homeostasis due to self-truing tendency.
A number of experiments performed in the past indicated that, for abrasive granule used in ultra-precision grinding, the grain diameter obey to truncated normal distribution, which means 99.7% of grains in grinding have size in [ max min, gg dd ].
Therefore, probability density function ( )gidP of grain diameter gid can be expressed as [4,8] ( ) max ggi min g 2 g ggi g 1 gi ddd; ;0 dd 2 1 exp 2 A dP <<                       − − = σ πσ (4) Where min gd and max gd is minimum and maximum grain size respectively, gσ is standard deviation and gd is mean which can be calculated by sieve number M and expressed as 1 2.15 − = Mdg [4,5,8], and 1A is test constant.
Numbers of such dressing tool topographies engage in the same place of abrasive, which work as an inerratic integral mode, made cutting edges equably at a certain level on the tool.
Hence, the grain protrusion number can be identified along with grain protrusion height hg by section height h and grain occurrence.

Thus, there is no simple relationship between the number of passes and the extent of the uniform elongation.
By contrast, there is a tendency for the flow stress to decrease with increasing numbers of ECAP passes.
Figure 2 shows the evolution of the Vickers hardness as a function of the number of ECAP passes.
It is apparent that the flow stress depends on the number of passes of ECAP and this dependence is not continuous.
Fig. 2 Evolution of microhardness in ZK60 magnesium alloy processed by different numbers of passes of ECAP Fig. 3 True stress-strain curves for the ZK60 alloy processed by different numbers of passes of ECAP.

Enhanced Formability of Ultrafine-Grained Aluminum Blanks by Local Heat Treatments M.
The high shear stresses during the rolling cycles result in an ultrafine-grained microstructure with an average grain size ranging between 200 to 1000 nm.
The extremely high plastification and the very high shear stresses during the rolling result in a very fine grained structure.
By repeating this process cycle, the grain structure can be refined more and more; depending on the number of rolling cycles the ARB blanks are referred to N1, N2, etc., where N1 stands for one rolling cyle, N2 for two rolling cycles and so on.
Moreover, the measured relative grain size increases match almost exactly the measured relative yield strength reductions as described by the hyperbola correlation of yield strength and grain size in the HallPetch law.

At the same time, the grain shape becomes more round as the temperature of airflow increases, and the holes between the grains also become smaller.
Fig. 1a shows that the average grain size was 54 µm, and grain shapes were irregular when the gas was not heated; Fig. 1b shows that the average grain size was 50 µm, and grain shapes were more regular than Fig. 1a when the gas was heated to 50 °C; Fig. 1c shows that the average grain size was 43 µm, and grain shapes were round when the gas was heated to 100 °C; Fig. 1d shows that the average grain size was 39 µm, and grain shapes were more round when the gas was heated to 150 °C.
The number and the size of holes decreases with the growth of temperature.
Where, M is airflow Mach number, M = Vg / ag; Vg is gas velocity; ag is the local sonic.
The grain round progressively and sizes of the hole decreased.

During the cooling process of annealing treatment, the number of β phases as perlite-type were increased with the furnace cooling time.
In the early stage of furnace cooling, the β phase nucleated preferentially in the grain near the boundary, only a small quantity of β phase precipitates.In the subsequent cooling process, the rate of precipitate about β phase increased remarked as the time of furnace cooling prolonging, the number of β phase increases dramatically, and the lamellar β phase evenly distributes inside most of the grain.
When the furnace cooling time further prolonged to 2.5h, the β phase continues to extend inside grain, and the lamellar β phase is basically formed inside individual grain.
Cooling to 3h，the number of β phase increases dramatically, and the lamellar β phase evenly distributes inside most of the grain.
But there is still a amount of un-decomposed area near the grain boundaries.

The results showed that the number and size of recrystallized grains increased with the increase of temperature at the same strain rate, and the number and size of recrystallized grains increased with the decrease of strain rate at the same temperature.
The dislocation increment rate will increase as the increase of strain rate at the same temperature, and a large number of deformation dislocations will be accumulated at the grain boundary soon, resulting in the increased of deformation resistance, so the peak stress will increase.
Microstructure Evolution and Recrystallized Grain Size of Mg-13Gd-4Y-2Zn-0.5Zr Alloy.
Therefore, the grain size model of dynamic recrystallized is as follows:
The grain size model of dynamic recrystallized is constructed as: .

Transparent Fine-grained Oxide Ceramics G.
Keywords: Alumina, Spinel, Transparent, Fine-grained.
This behaviour is counter-intuitive as decreasing the grain size increases the number of grain boundaries from which scattering can occur.
TEM microsgraph of fine grained MgAl2O4.
The grain boundary scattering in RE-doped Al2O3 samples was exacerbated by the increased grain size distribution.

Since superplasticity is a grain size dependent phenomenon.
Over the past decades, there have been a number of attempts to reduce grain size of the materials to submicron- or nano- level so as to achieve high strain rate superplasticity and/or low temperature superplasticity.
The nickel grains mostly remained in equiaxed shape.
During the deformation grain boundary sliding takes place between nickel grains.
When heated to high temperature, the significant sulfur segregation at grain boundaries occured and reduced the strength of Ni-Ni bonds, the effect of which is to inhibit grain growth and to enhance grain boundary sliding.

Insect infestation is a common problem for stored grain.
Its application to grain with the aim of detecting insect infestation is gaining popularity [11-13].
Different from the BP neural network whose structure has to be artificially designed, SVM automatically determines the required number of hidden units (the number of support vectors, SV).
Experiments and Result Grain samples .
The first group of grain was 2kg un-infested wheat, labeled Sample0.

Important grain size dispersal was observed and a heat treatment was successfully applied on sheets to diminish the grain size and improve the superplasticity of the sheets. 1.
Consequently an investigation with optical microscope was done in agreement with the French specification NF A 04-503 and revealed a non conformity in the grain size : the indicator of the grain size was 8.5, which means that grains were bigger as the maximum size specified.
However grain size is a key characteristic for superplasticity and the cavitation effect is delayed with smaller grains for superplastic forming of aluminum alloys.
The grain size testing is specified as a periodic test – 2.
Results from average grain size computation on non treated and heat treated samples Sample Longitudinal direction Normal direction Non treated Average grain size 24.5 µm 11.9 µm Number of measurements 136 338 Heat treated Average grain size 16.5 µm 8.5 µm Number of measurements 214 523 About superplasticity improvement of aluminum 7475-T4 after heat treatment As the applied heat treatment resulted in a significant grain refinement, we investigated the impact of this refinement on the aluminum 7475-T4 superplasticity with a tensile test.