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The obtaining of dense and fine-grained structure of silumin with the release of excess phases in a compact form provides the desired property level of aluminium products.
Among the systems of engineering analysis [6-13], the most required is the ProCAST finite-element system using the maximum possible number of varied technological parameters and, thereby, simulating all stages of foundry, with the exception of smelting.
The average grain and dendrite size was evaluated on one of the cube’s faces by using the Thixomet software and hardware system.
In doing so, the average grain size was Dav=5.338 mm, and the average dendrite size was dsp = Dav/18.3 = 395 μm.
Based on the above method of calculating the average sizes of dendrites and silumin grains, and the evaluated regularity of the influence of electromagnetic field on the nucleation process, a computer program forecasting the structure of aluminium alloy was developed [17].

Accumulative roll bonding(ARB) is a kind of severe plastic deformation (SPD) method，which can be used for the continuous production of ultra-fine grained metallic multilayered composites [7-9], and the multilayered composites of different materials can be produced through the ARB processing.
The SEM samples were sectioned, cold mounted, polished by silicon dioxide paste with grain size of 1μm and finally etched in nitric acid and alcohol mixed solution, and then examined by using a scanning electron microscopy (SEM,JSM-6480) with energy dispersive spectroscopy (EDS,INCA).
As for the low strain amplitude, the damping values of sandwich plate and 1 pass rolling are higher; it is because that when conduct accumulative roll bonding deforming, the composite plate generates large numbers of broken sub-grain due to the deformation, the dislocation density inside the crystalline grain is higher, and then the mutual entanglement and interaction between the dislocation generates bigger influence on the damping.
While with the increasing of rolling deformation amount, the crystalline grain is gradually uniform without apparent refinement and the movable dislocation density reduces.
With the increase of rolling deformation amount, the dislocation in AZ31 layer entangles and the crystalline grain continues to shrink, which also makes the damping capacity reduces.

The fine carbides precipitated also prevent the growth of the austenitic grain during the cooling, contributing to the increase of the toughness.
When added together with the niobium, molybdenum increases the number of Nb(C,N) particles and they are finer, which increases the potential for the precipitation hardening [5].
Table 3 – Pearlite interlamellar spacing, Vickers hardness and austenitic grain size after isothermal treatment at 650 ºC.
Steel 7C 7NbMo 7V Interlamellar Spacing (µm) 0.19 ± 0.02 0.26 ± 0.03 0.15 ± 0.02 Vickers Hardness (HV) 333 ± 2 303 ± 12 354 ± 4 Austenitic Grain Size (µm) 12 ± 1 8 ± 1 6 ± 1 The 7V and 7NbMo steels presented smaller AGS (Austenitic Grain Size) than 7C steel (6; 8 and 12 µm, respectively), due to the precipitation of fine V, Nb, Mo carbonitrides during the forging process, which pinning the austenitic grain boundary and difficult its growth (Table 3).
The 7V and 7NbMo steels showed smaller AGS (Austenitic Grain Size) than 7C steel.

It has a wide spread all over our country, which makes more 90 percent of the total number of the world [3].
The conical flasks were in series and numbered, which formed one Multi-stage Countercurrent Extraction tank group in each group.
Take for example, the coarse group. 4 equal conical flasks were in series and numbered as ①, ②, ③ and ④ successively.
The one numbered as ④ was the head tank that provided transudation, which was laid up for subsequent processing.
Residues can be divided into two parts based on grain diameters.

Studying the dispersion of the material, a number of signature features can be distinguished: the size and shape of the particles; the intensity of interphase interaction; the possibility of adhesion between particles [10-14].
The dispersion of a material at the micro level is characterized by a number of features while at the macro level it is defined by the degree of material fragmentation into tiny particles.
Dune sand grains before grinding Grains of dune sand after 20 minutes of grinding (magnification 500 times) Fig. 2.
Kuzmin, Fine-Grained Concrete of Composite Binder.
Bisultanov, Fine-Grained Concretes with Clinker-Free Binders on an Alkali Gauging (Fine-grained concrete based on alkaline activated binders), Proceedings of the International Symposium "Engineering and Earth Sciences: Applied and Fundamental Research" (ISEES 2019).1.

Also the reinforcements tend to settle at the grain boundaries and act as diffusion barriers to the copper particles during sintering which in turn results in porosity.
The Cu(Al) interface exhibits ultra-fine grain structures and the mechanism involved in the grain refinement is not yet understood [10].
From the dark borders of copper particles in Fig.4 (b), it is evident that Graphene occupies the grain boundaries of copper.
It is understood that any reinforcement to copper would get settled in the grain boundaries and results in grain refinement [2,11].
However, the lower conductivity values can be found in the samples sintered at 900°C and this can be correlated to the presence of more number of voids comparatively

We have each session vectorized and each session is encoded as an N-dimensional binary attribute vector where N is the total number of different query terms during all sessions.
Similar to the term similarity matrix, we construct a k-dimensional symmetrical matrix to represent the similarity based on URL and k is the number of different URLs clicked.
Then obtain a=0.545, when the number is four, a=0.48.
MAP is the mean value at some point, namely sum of precisions at one certain threshold divided by the number of groups in our experiment.
And in Fig.2 it has been shown that if the merge similarity is set too high, the number of clusters generated will be too large and may equal to the number of the users, this will result in coarse-grained clustering; if the merge similarity is set too low, many irrelevant users may be classified into the same cluster, and this will result in fine-grained clustering.

When the transgranular fatigue cracks combine with the grain boundary voids, the fatigue creep will promote each other and form the creep-fatigue interaction [6, 7].
The results show that the fracture mechanism of 1Cr1MoV steel is transgranular fracture with obvious fatigue bands and no creep voids formed at grain boundaries.
And short-term creep only is a process of dislocation slip, which results in dislocation plugging, stacking fault, twins and other structures, without obvious damage to grain boundaries [13, 14].
The statistical data of thermal recovery casing failure show that necking fracture is the main form of failure, which accounts for nearly 50% of the total failure number [15].
After meeting the strain limit of the current cycle, the number of thermal recovery rounds is added to 1, and then the strain of the next thermal cycle is determined.

The lower the temperature, the more diffusion along grain boundaries should become the major transport mechanism.
Then, grain size distribution evolution in the oxide should be taken into account.
Indeed, a larger number of dislocations leads to a higher vacancy annihilation capability.
As a consequence, the decrease in the number of defect not only lowers the diffusion rate in the metal but also leads to a reduced tendency for vacancies to accumulate and cause local scale detachment.
Since these first models which take into account only a volume diffusion mechanism, various models challenge to connect microstructure and oxidation rate, considering processes like the effect of stress on diffusion [10], grain boundary diffusion [11].… However, they always presume that a pseudo-steady state is reached.

Different ECAE routes are designated as: A, no bar axis rotation; C, 180° rotation after every pass; BA, clockwise 90° rotation after even numbered passes and counter clockwise 90° after odd numbered passes; and BC, 90° rotation after every pass.
The average grain size of this material was ~100 µm.
The rotation angle remains nearly same for each of the routes, irrespective of the number of extrusion passes and the accumulative strain.
A very recent study by Cao et al. [11], who also studied commercially pure Al (99.5%) deformed by route Bc, reveals that texture becomes stronger with number of ECAE passes.
However, it can also be due to the formation of new grains with rotated cube orientation as a result of dynamic recrystallisation.