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Usually the fly ash is primarily composed of coarse particles（50～10μm）, sand （100～50μm）, a few fine particles（5～2μm）and finer-grained size（<2μm）.
The distribution range of the H fly ash is relatively narrower and the mean grain size is larger.
Then the continuity of the grain is better.
The plasticity of the mixture is greatly influenced by the grain composition, particle size, and distribution range of particle of fly ash [3].
The bigger of the difference between DM and D50, the larger of fine solids and viscous grain content is, and then the mixture plasticity index is increased.

The scientific community has accumulated a number of studies aimed at determining conditions for the formation of thin tapes with a microcrystalline structure during spinning [13], but it is impossible to assert that the issue has been sufficiently studied.
Pressure, MPa Mold rotation speed, rpm Tape width, mm Tape thickness, microns 1 0.9 1200 27 30-40 2 0.3 800 27 20-30 According to the spinning modes, two types of tapes were obtained; designation of the samples, upon further examination, corresponds to the numbers of the modes from Table 1.
In this work, the grain structure of tape samples was analyzed by the method of reflected electron diffraction (RED) in a Tescan LYRA 3 scanning electron microscope (SEM).
Figure 4 shows histograms of grain size distribution.
Histograms of grain size distribution in tapes 1-a) and 2-b) The average grain size for sample 1 is 2–4 µm, for sample 2 this value is in the range of 3–4 µm, while the maximum grain size distribution in sample 1 is shifted to the region of smaller values (Figure 4 a), and in Figure 4 b) there is an additional peak corresponding to a size of 6-7 microns.

Development of technology for its processing will allow to solve a number of resource saving indicators, namely, management of resources and utilizability.
The number of medium inclusions is 45.7 wt. % By material composition, the coarse-grained inclusions in clay are presented mainly by quartz, limonite, and by dolomite in a small amount.
The plasticity number of clay according to Vasiliev’s method is 10.
To determine the technological properties of clay, the clay powder was ground to a grain size of less than 3 mm.
To determine the effect of clay grinding on the sintering degree, we use clay powder ground to a grain size of less than 0.5 mm.

Analysis of the data published in Russian and foreign papers showed that in spite of a large number of technical solutions developed by domestic and foreign specialists and in spite of the high efficiency of some of them, a number of scientific, technological and manufacturing problems have not been solved yet [1 – 5].
Experimental Part The developed method implies a number of application options.
As a result an additional shear of closely orientated grains occurs along their boundaries and they are refined due to crushing.
At the same time significant elongation of grain boundaries takes place, which makes it possible to provide deeper processing of the metal structure.
Ultra-fine Grain Materials by Severe Plastic Deformation: Application to Steels.

Figure 3b shows the bind zone, the microstructure is mainly proeutectoid ferrite (GBF), a small amount of pearlite (P), granular bainite (BG) and acicular ferrite (AF), The side grains near the weld zone are smaller, and the side grains near the overheating zone are coarser.
The main feature of the microstructure is that there are more acicular ferrite (AF) and proeutectoid ferrite (GBF), and a small amount of pearlite (P) and granular bainite (BG) structure, no ferrite side-plate (FSP) with poor plasticity growing into the grain boundary was found, and the grain size was relatively uniform.
The fiberous area of G40X is mainly small dimples, and the local small dimples are shallow, The radiation zone is mainly characterized by a large number of quasi-cleavage and cleavage; the shear lip is mainly composed of a large number of dense short tearing edges, and the dimples are few and shallow[11].
The dimples in the fibrous zone of G40X are small equiaxed dimples with flat bottoms, and the radical zone is mainly characterized by a large number of quasi-cleavage and cleavage features; the shear lip zone is mainly a river pattern, accompanied by a large number of dense short tearing edges.The radiation zone of G40Y is mainly quasi-cleavage, and the cleavage steps are low.
Conclusion (1) The appearance of the welded joints in the two working conditions is good, and the microstructure characteristics of the welded joints are observed and analyzed, it is found that there is little difference, The main feature of the microstructure is that there are coarser bar-like proeutectoid ferrite (GBF) and more acicular ferrite(AF) distributed at the prior austenite grain boundary.

Increasing the number of B atoms leads to increase in the B-B bond strength and results in an increase in melting temperature, hardness, strength and chemical stability.
Fig. 3a shows the typical grain boundary structure of polycrystalline TiB2.
The microstructure is composed of clear grain boundaries without any second phase.
The liquid phase enhances the mass transport, but causes accelerated grain growth.
TiB2 cermet surface consist of large grains of Fe3Ti3O10 and spheroidal grains of TiO2 after the oxidation at 850 o C for 70 h (Fig. 9a) [93].

Since the discovery [1] and the following analysis by Darken [2], this effect assumed a prominent role in the diffusion theory, and its manifestations have been explored in a large number of carefully controlled experiments.
Analogously, p and q are the number of moles of Co- and Si-atoms transported during interaction across unit area of the CoSi, and r and s are the number of moles of Co- and Si-atoms transferred across unit area of the CoSi2 - phase layer.
Owing to high atomic number of Th, these particles exhibit a distinct "white contrast" on backscattered electron images.
Duplex grain morphology in the reaction product layers on either side of the Kirkendall plane(s) is clearly visible in (a).
Note that the apparent "waviness" of the interphase interfaces also reflects the difference in the growth rate from grain to grain resulting from the difference in crystallographic orientation.

Equations of a semi-empirical Sellars-type model to describe coupled evolution of flow stress and grain size.
All other increments proceed with the same number of iterations in both FE simulations.
Cahn showed that transformations which originate from the grain boundaries, edges and corners initially proceed with a growth exponent of 4.
After all grain boundary nucleation sites are occupied (“site saturation”), the transformation proceeds with a growth exponent of 1.
Then, nucleation should proceed at the interfaces between unrecrystallized and recrystallized grains.

As shown in Fig.2, the as-cast alloys display coarse grains and poor composition homogeneity.
The grain refinement is beneficial for it, whereas added internal stress and lattice distortion are unfavourable.
The refined grain produced by the rapid quenching accelerates the diffusion of hydrogen atoms in the alloy.
The cycle life was defined by the cycle number after which the discharge capacity of the alloy at a current density of 600 mA/g is reduced to 60% of the maximum capacity.
The grain refinement did not engender obvious influence on the anti-corrosion performance of the alloy.

Based on the peculiarities of the methods of obtaining spherical powders in order to obtain spherical granules of a regulated grain size, the technology of electroerosive dispersion, which is distinguished by relatively low energy costs and ecological cleanliness of the process, is proposed.
Grinding produced metallographic paper with a large (№№ 60-70) and fine grain (№ № 220-240).
Image processing in “SIAMS Photolab” is performed in a chain of interconnected cells containing the original image, the results of intermediate processing steps, the final processed image and the measurement results in the form of numbers, graphs and histograms.
The histogram in coordinates q3 (x) = f (μm) (right scale) - the number of sample with a given particle size.
Project number is 17-79-20336.