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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.

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.

Their characteristics by fractional composition are proposed: large-fractional, with grains from 2 to 150 mm in size, medium-fractional with a grain size of 0.5 to 2 mm, and fine-grained with a grain size of 0 to 0.5 mm.
Comparing the grain composition of MFMSHP to GOST 8736-2014 "Sand for bilding works.
Comparing the grain composition of MFMSHP to GOST 25100-2011"Soils.
Classification" they fall into the group of sand grains ranging from fine to coarse grain mainly containing medium ones.
Studies have shown that there is certain correlation between the amounts of coal at different fractions: its lower number is contained at fractions of >0.63mm, average number at fractions of<0.16 mm and a greater number at fractions from 0.16 to 0.63mm.

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.

According to iconic two-dimension grain-size analysis, and contacting to fundamental sedimentary characteristics of conglomerate, sedimentary environment analysis is carried out.
Grain-supported type is mainly matrix support structure and grain-supported structure.In the matrix support structure, the matrix content is high, gravel particles are generally smaller and the particles in the matrix is floating.In the grain-supported structure, between the particles varieties of contact manners existed, the common are wired contact, bump contact and stapling contact, but also a bit point contact.
Through the comprehensive study of the large number of samples, sediment grain size probability cumulative curves in the study area are mainly the following three types
The type of granularity probability curve is similar to turbidites granularity probability curve, mainly reflected the characteristics of the grain size of mudslides and debris flows
Accordingly identify the total of 9 categories lithofacies that are linear grain-supported matrix-free massive bedding solution pores conglomerate phase(Gclm), linear grain-supported fine gravel matrix massive bedding mid-conglomerate phase(Gmclfgm), point-type grain-supported coarse sand matrix massive bedding uniform mid-conglomerate phase(Gmctcsm), point-type grain-supported coarse sand matrix massive bedding mid-conglomerate phase(Gmctcsm), matrix (grit) supporting massive bedding mid-conglomerate phase(Gmmcsm), point-type grain-supported coarse sand-fine gravel matrix massive bedding mid-conglomerate phase(Gmctcs-fgm), single coarse conglomerate phase(Gc), all kinds of coarse sandstone phase and various types of mudstone

The samples were further characterized with electron back scatter diffraction (EBSD) to examine the grain size.
Equal channel angular pressing (ECAP) can refine grains effectively and consolidate the powder materials into bulk ultrafine-grained materials (UFG) without residual porosities under low deformation temperature (below the recrystallization temperature).
In addition, the grains are well refined that the average grain size decreases from 0.43 µm to 0.24 µm with the increasing number of ECAP passes.
Shear strain make the majority contribution to the improvement of relative density and coordination number.
The results demonstrate that grains are refined to 0.24 µm by 2 passes of ECAP processing.

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 number of deformation steps was 12.
Number of compression steps 0 2 4 6 8 10 12 , µµµµm 0 2 4 6 8 10 12 14 16 a b Fig. 1а.
Typical microstructure formed at high values of accumulated strain (4 compression steps) - а; effect of the number of compression steps on mean grain size (b).
Discussion A decrease in the mean grain size by approximately two orders of magnitude (Fig 1b) means the nucleation of a great number of new grains during strain and allows classifying the process under study as dynamic recrystallization.
The large number of dislocation boundaries, the gradual increase of high angle boundary content and the presence of twins (Table 1) mean that the nucleation of new grains occurs via the formation of deformation-induced boundaries (dislocation and twinning ones) and their subsequent evolution.

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.

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.