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Grain size of cast alloys was determined using an image analysis system from a large number of measurements.
However, grain can be refined and solidification range can be also reduced by RE additions, resulting in better fluidity [9-11].
Fig. 5 indicates that the fluidity is improved and as-cast grain size is reduced in RE-added alloys as compared to the base alloy.
This fluidity enhancement seems to occur due to the reduced solidification range and grain size.
The as-cast grain size was reduced by the additions, and the fluidity was significantly enhanced.

The maximum ratio of high-quality grains is produced mainly after contact of the dry fly-ash with large water droplets when there is immediate linkage of grains.
At the plate, grains with a practically constant cross section are created according to the requirement for graining.
Properties of the tested aggregate From the resulting raw material mixture, the sufficient numbers of samples of the artificial fly-ash aggregate were created with the fraction 8-16 mm, either on the granulation plate, as well as on the cylindrical granulator.
It is stated either by the compact character of grains, as well as their form.
As it was shown on tests carried out on cold hardened granulate, more quality grains originate by the production of the granulation plate, and using this manner of pelleting more compact grains originate with the compact firm structure.

As an etchant for identifying of grain structure Murakami etchant was used [10].
Fig. 3 shows that the ceramics has a dense, uniform fine grain structure with equiaxed grains.
The grain size is 1.5-3.5 microns.
The result can be related with increasing of ceramics density and a homogeneous fine-grained structure creation.
This assumption is based on the inverse relationship between the material strength and the grain size and also on fact, that formation and growth of critical size cracks in materials with fine-grained structure is inhibited owing to a small size of the structural fragments and a large number of boundaries.

During superplastic deformation the materials will produce a large number of micro-defects, such as dislocation, vacancy and micro-voids and so on.
The grain size and dislocation density can be observed by the transmission electron microscope (TEM).
First, the extrusion process can refine the crystalline grain, so that the capture ability of the grain boundary is increased.
Especially when the grain size is smaller than 1mm, the positrons are trapped by the grain boundary and there is greater contribution to the lifetime increase of positron annihilation.
By comparing the lifetimes of the pure aluminium, extruded Al-12.7Si-0.7Mg alloy, and Al-12.7Si-0.7Mg alloy after the heat treatment, it may be concluded that the existence of a large number of grain boundaries and dislocations results in the apparent increase of the positron annihilation lifetime value for the extruded alloy.

Introduction Shiwu Fault Depression is located in the southeastern edge of the Southeast Uplift in Songliao Basin.It is a composite superposed basin,composed by Huoshiling formation,Shahezi formation,Yingcheng formation and Denglouku formation in deep strata.Currently,we have found Houwujiahu,Bawu,Gujiazi,Pijia,and Siwujiazi gas fields,Qinjiatun and Taipingzhuang oil-gas fields as well as several oil-gas structures.However,a large number of exploration results show that in deep strata reservoir heterogeneity is extremely strong, distribution and main controlling factors of deep clastic reservoir are unclear.Different lithologies have different hardness,density composition,structure constitute and other attributes,which affects not only the size and type of primary pore,but also diagenesis and the size and type of secondary pore.Therefore,the study of clastic petrology features in the study area is of great significance.
Shahezi Formation Reservoir.The reservoir rocks can also be divided into two types of clastic reservoir rocks and volcanics reservoir rocks.Shahezi Formation clastic reservoirs are mainly feldspar sandstone and cutting feldspar sandstone.In the detrital grain,the content of quartz is relatively high,an average of 48.2%,feldspar accounts for 38.8%,the proportion of debris is 13.0%.Main components of reservoir are glutenite,medium-coarse pebbled sandstone,medium sandstone and fine sandstone,their textural maturity is moderate.Calcite is the main component of cement,general content is between 4-26%,with the individual upping to 40% and an average of 11.46%.A small amount of silicalite mostly emerges in the form of secondary enlargement,main cementation type is pore,then hybrid.Matrix content is medium,general between 2-20% with an average of 7.77%,and mudstone mostly presents film-like with recrystallization.Detrital grain are linear and asperities inter-granular contaction.
form of intergranular filling.Detrital grain are linear and point inter-granular contaction.
grain are mainly linear and point inter-granular contaction,a few scabrate-consertal cantaction.
Figure.3-1 Distribution of sizes in Shiwu Fault Depression reservoir Figure.3-2 The relation of hydrocarbon and distribution of grain size Size pattern of clastic rock Fig.4 is the content diversification of Shiwu Fault Depression reservoir interstitial materials.The reservoir interstitial materials are mainly matrix and cement.

The size and shape of dimples are governed by number and distribution of nucleated micro cavities and by stress internal level present in the material.
The microstructure consists of equiaxed α (HC) grains with average size about 10 µm.
The β (CCC) phase is present in the α grain boundaries.
The micrographs show the grain growth of the alpha phase and beta dissolution; based on the initial microstructure before test it was continuous along grain boundaries.
The size and shape of dimples are governed by number and distribution of nucleated microcavities and by stress internal level present in the material.

Weldments were made of ultra-high strength fine-grained steel S700MC produced by Voestalpine Stahl GmbH, Austria.
The number of passes with their distribution is also shown schematically in Tables 2 to 5.
Using every welding mode (Tables 2 to 5) two plates were welded so the total number of the welded plates was eight.
For maximal impact toughness of weldments a suitable number of passes is recommended depending on the welded parts thickness; when this thickness is 8 mm the recommended number of passes is between 3 and 4 [2].
As the increase in the welding gap from 0 mm to 8 mm leads to an increase in the number of welding passes from 2 to 6, the welding gap increase has as a result a reduction in the dimensions of partially melted zone and of the grain size in this zone.

If a calculation of residual stresses weren’t run: *.inp – the mesh; *t.unv – temperature; *c.unv – the porosity index; *f.stl – the shrinkage hole geometry; *m2.unv – the average grain size.
For this reason during the saving key-files produced the recalculation of the density index using the following algorithm: , (1) where n is number of element, consisting of i, j, k and l nodes; is the relative density (key-file); is the relative porosity (unv-file).
By default, the measurement unit of the grain size is centimeters in ProCast, and in Deform-3D are microns, so during the transfer it is performed the conversion of units.
Furthermore Deform-3D feature is that for operation with grain size data is using the information about the properties of the material, namely the Avrami model parameters, which defines the recrystallization process.
The grain size distribution, microns a b Fig. 5.

The results show that: The vertical deposition samples exhibit coarsen epitaxial columnar grains and the parallel samples show equiaxed grains, and microstructure are basket-weave α+β phase.
The T-S orientation and S-L orientation were mainly composed of coarse primary β - columnar grains.
At the same time, part of continuous α phase was distributed in the original β grain boundary, which was due to the alloy was treated by HIP.
Therefore, the tensile strength and yield strength of the sample parallel to the stacking direction, the sample with the largest number of layers, had the lowest tensile strength and yield strength [12].
Therefore, the anisotropy of mechanical properties of ZTC4 alloy in this paper was mainly related to the grain orientation.

θhkl -- the right half of the incidence Angle 2θ Fig 2 is Cu30SiC70 SiC grain size in the time of ball mill are curve.
So the start of the ball mill of the SiC grain size decrease quickly.
Ball mill after 20 h, the grain size decrease rate reduced.
Fig 2 SiC grain sizes and the millling times relationship Fig 3 Cu grain sizes and the millling times relationship Due to attract a large number of defects in the process of mechanical alloying and surface energy, refining grain size, this makes the original balance of lattice in a state of imbalance, it will cause the change of the SiC lattice constant, lattice constant alpha can be calculated by formula (2).
[2] Cu30SiC70 after high-energy ball mill the grain size is reduced quickly, but after 20 hours of Cu grain size decrease after high-energy ball mill in the SiC grain size with ball milling time has been reduced