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During procedure and heat treatment of magnesite in shaft and rotary furnaces, a great number of fine fractions are generated.
A large number of fine-grained materials or dust particles with very good chemical composition are formed during the extraction and heat treatment of magnesite.
· In SF, the fine-grained material is in the fluidized state less intensively.
In the product mechanical separation, the grain size fractions with different loss on ignition can be obtained Conclusion The development of microfluid furnace was based on the knowledge gained from the laboratory experiments and physical modelling of the processes of fine-grained material treatment in a microfuild furnace.
The microfliud furnace current research is focused on the fine-grained material thermal treatment in the magnesite extraction and processing.

Since the initial positions of particles can significantly influence the simulations results, a random, isotropic distribution of grains with realistic coordination number and radial distribution function is used.
The initial density is set to 60% and the initial coordination number is 6.1.
Voigt gives an upper-bound for G/K of 0.6 that is independent from the coordination number [22].
The increase in G/K if grain rearrangements are possible is an indicator that because of an increasing coordination number the grains become more stable against shearing.
This coordination number dependence is also captured in the self-consistent estimate, which gives a G/K ratio of 0.27 for a bcc structure with a coordination number Z = 8 [22].

Grains modelling.
Fig.1 shows the results of the computational homogenization for BaTiO3 performed by computing volume averages of the micro-fields over aggregates containing different numbers of grains.
Fifty morphologically different random realizations are generated for each selected number of grains, which are assigned random spatial crystallographic orientation.
For each realization the volume averaged values of the apparent shear modulus and relative dielectric constant are plotted versus the number of grains in the aggregate; ensemble averages are also shown.
Moreover, since only meshing of the grain boundaries is required, simplification in data preparation and reduction in the number of DoFs are attained, with consequential computational benefits.

The parent alloy casting sample was an equiaxed structure with a grain size of 15–60 μm and contained a large number of eutectic phases at the grain boundary (Fig. 3(a) and (b)).
According to Figure 4(a), the master alloy casting sample is an equiaxed structure, and there are a large number of skeletal eutectic phases at the grain boundary with a width of ~2–10 μm, which are evenly distributed along the grain boundary.
From Figures 5(a) and (c) and the energy spectrum analysis, a large number of Al3Ti phases (needle-like and with a massive structure) and TiC phases (granular) are distributed in the alloy casting, and the grain size is between 10 and 200 μm.
Acknowledgments Foundation item: This work was supported by the National Natural Science Foundation Project [number 51661031; 51861033].
Microstructure and formation mechanism of grain-refining particles in Al-Ti-C-RE grain refiners[J].

Permanent mold cast (PMC) AJ62 magnesium alloy exhibits a fine-grained microstructure in the thin section and a coarse-grained microstructure in the thick section.
The corrosion behaviors in the fine- and coarse-grained AJ62 alloys were compared.
Integral to an alloy’s adaptation to a new process is the characterization of the alloy’s performance in a number of potential environments.
The chemical additions used, and number of them, also vary from one coolant producer to another and are not information readily disclosed.
The fine microstructures are found to form in the thin section of the casting due to a high cooling rate while the coarse grains are present in the thick part.

This value decide about number of generated defects, which are with increase deformations changing theirs localization, which leads to creating new nanometric size grains.
When deformation value are bigger fragmentation grain process is much more slower and strives to specified grain size limit.
Increased number of passes to obtain required results, samples were subjected up to 9 ECAP passes.
As much as grain size and type of grain boundary depend on material properties and process conditions.
To compare grain sizes after the same number of passes and the same section (Figure 1c, 1d, 1e and 1f) are shown.

Some grains were not smashed thoroughly, but curved and necked down, and a large of grains with fine, homogeneous and spheroids presented at 570°C (Fig.1b).
When the stirring speed was slower, the grains became larger.
When the stirring temperature was too lower, the grains grew up and got together, which made the grains coarsening and the mechanical properties reducing.
The smaller the grain size, the larger the area of grain boundary, the greater the numbers of different orientation around each grain and the plastic deformation resistance were.
The deformation could disperse into more grains.

a) Band contrast EBSD map of the microstructure of a titanium stabilized 409 ferritic stainless steel after cold rolling to 50% reduction followed by annealing at 750oC for 200s illustrating the unrecrystallized bands (numbered 1,2 and 3) of a-fibre oriented grains.
(1) Growth of the recrystallizing grains within the deformed a-fibre grains occurs concurrently with 1) recrystallization by “nucleation” of new grains within a-fibre regions and 2) growth of recrystallized g-fibre grains into the still deformed a-fibre grains.
One assumption is that planar growth (eqn. 2) controls the growth of g-fibre grains into a-fibre grains.
Unlike the JMAK model where continuous impingement of grains is assumed, in phase field simulations consisting of a limited number of nuclei, impingement does not commence until a significant fraction recrystallized has been achieved.
Thus, in the phase field simulations prior to impingement the fraction recrystallized varies as [14], (6) where is a geometric constant, is the number of nuclei per unit volume, is the (constant) rate of interface migration and n is the growth exponent, which for site saturated nucleation is the same as the JMAK exponent.

Grain Emergency Transport Model on Unascertained Number GAO Youjian1, a , LIU Guangli1,b and LI Di1,c 1 China Agricultural University, Beijing, China a 317882655@qq.com, b liugl@cau.edu.cn, clgl7109@163.com Keywords: Unascertained Number, Emergency Transport, Algorithm Abstract.
The question to choose a grain supplement emergency path is uncertain.
Between this place and the grain bins around, there are still some roads to choose.
The expectation is a real number which cannot operate with interval number, so we can consider that put these two kinds of numbers into a wider range which called grey number.
Research on Grain Logistic Distribution in Times of Emergency.

The microstructure of the as-deposited sample consisted of columnar and equiaxed grains, in which siliconwas distributed along the grain boundary and the grain size was about 30 μm.
Besides, some TiB2 particles converged at the grain boundary.
Besides, there was a clear division between coarse and fine grains in two directions.The existence of coarse grains and fine grains is related to the solidification process.
The reason why TiB2 particles can refine grains during solidification is that TiB2 has some co-lattice relationship with α-Al, so a small number of TiB2 particles can become the heterogeneous nucleus of α-Al, while other TiB2 particles will hinder the growth of nascent α-Al grains, thus realizing the refinement of grains [18].
According to the analysis of scanning electron microscope images (as shown in Fig. 5), the size of TiB2 particles was generally less than 1 μm, but the size of a small number of TiB2 particles could reach about 2 μm.