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The effect of a highly dispersed wollastonite-based additive on the physical and mechanical characteristics of fine-grained concrete was studied by uniform test procedure according to regulatory documentation preparing fine-grained concrete samples 40×40×160 mm in size.
It is established that the fine-grained concrete modified with the wollastonite Miwall 05-97 shows the best characteristics.
The compressive strength of the fine-grained concrete modified with the obtained compositions of a highly dispersed additive is given in Figure°3.
It contributes to the production of the effective fine-grained concrete with the Portland slag cement CEM II/A–Ш 42.5H as a binder, having the compressive strength of 50.8 MPa, and an additive content in the composition of fine-grained concrete in the amount of 10% of the cement weight.
Karpikov, Energy-efficient fine-grained concrete with integrated microfill, Construction and reconstruction. 5 (2014) 94–100

Crystal clusters in the overheated zone were dominated by secondary α phase (dark-colored) (Fig. 2a2 and Fig. 2b2), and a large number of microcracks were generated at the grain boundaries (Fig. 2c2).
A large number of primary α equiaxial grains were distributed near the overheated zone, and the grain size was about 210±10 μm (Fig. 4a2-4a4 and Fig. 4b2).
Differently, a large number of secondary α equiaxial grains were distributed near the heat-affected zone, with a grain size of about 80±20 μm (Fig. 4a2-4a4).
It was worth noting that a large number of microcracks appeared at the grain boundaries between crystal clusters of primary α phase and secondary α phase in the overheated zone and melting zone (Fig. 4b1 and Fig. 4c1-4c2), and the extension direction was consistent with the grain boundary.
The primary α phase and secondary α phase crystal clusters were evenly distributed near an overheated zone, but a large number of secondary α equiaxial grains were distributed near a heat-affected zone, with a grain size of about 90±10 μm.

The fine-grained concrete without any reinforcement additives will have the minimum water absorption (3%).
Introduction Fine-grained concretes take a special place in modern construction.
However, in spite of all the advantages, they have a number of shortcomings, i.e. low bending strength, high shrinkage when hardening and, as a result, crack formation [1].
The fine-grained concrete without any reinforcement additives is distinguished with the minimum water absorption (3%).
Karpikov, Energy-efficient fine-grained concrete with integrated microfill, Construction and reconstruction. 5 (2014) 94–100

The grain size and lamellar spacing obey a parabolic law.
The alloy exhibits mainly a uniform near lamellar (NL) structure with a large number of lamellar colonies composed of γ-sheet spaced by α2-sheet.
It should be noted that there is a random distribution of the borides showing white ribbons or particles in both grain and grain boundary.
Thus, the number of γ phase nuclei increases, the size and amount of γ phase gradually increase with increasing content of tungsten.
Acknowledgements This research was sponsored by the National Natural Science Foundation of China (project number 51201141).

The Ti-V-N steel has the lowest mean prior austenite grain size, where the prior austenite grains are distributed in bands of coarse and fine grains.
Single phase cuboidal (Ti,V)(C,N) particles were observed in all four steels, but in much greater numbers in the Ti-treated steel.
Nevertheless, the Cr-V-N steel, has a large number of individual and fine (Ti,V)(C,N) particles.
Histograms showing the number density of (a) (Ti,V)(C,N)- and (b) Mn-Al-(Ca) silicate-containing single or multi-phase inclusions.
V-N 50 and 25 exhibited similar inclusion populations, however, Cr-V-N presented a high inclusion number density of (Ti,V)(C,N)-bearing inclusions (Fig. 2).

It is known that grain boundary properties are strongly dependent upon the types and structures of grain boundaries [1].
The GBCD (i.e., grain boundary misorientation and grain boundary character distribution) was measured by the electron backscatter diffraction (EBSD) technique.
The Co-33Ni alloy (Fig.1b) shows a recrystallized microstructure consisting of a mixture of coarse grains and fine grains.
A great number of annealing twins are observed in the recrystallized microstructures of both the Co3Ti and Co-33Ni alloys.
RD TD crostructure consisting of equiaxed L12 grains, while Ni-25Fe(D) (Fig.1d) show a recrystallized microstructure consisting of fcc grains.

Square boundaries of the grain were parallel to (100), (010) or (001).
Finally, the dislocation motion stopped at grain boundaries.
The stress of each model increased again at εx 5 106 − ×= because the mobile dislocation reached the edges of the model grain (i.e., grain boundaries) as shown in Fig.2.
Dependence of the critical stress on the number of network sheets is presented in Fig.5.
Fig.5 Relationship between the critical stress and the number of network sheets.

These bars were cut into billets with lengths of ~65 mm and numbers of disks were sliced from the billets and polished to achieve uniform thicknesses of ~0.83 mm.
It should be noted that the error bar on each datum point represents the standard deviation of the numbers of measurements.
Valiev, Deformation behavior and plastic instabilities of ultrafine-grained titanium, Appl.
Mohamed, Mechanical properties of an ultrafine-grained Al-7.5 pct Mg alloy, Metall.
Valiev, Grain boundaries in ultrafine grained materials processed by severe plastic deformation and related phenomena, Mater.

It was found that post heat treatment could reduce the number of pores existed in the aluminum coating.
The resulted Al spray coating exhibited large defects including number of voids and pores due to incomplete inter-splat contact or numbers of un-melted particles, which is consistent with the results of Gao's report [5].
Thus, diffusion in Mg-Al system appeared to occur along the grain boundary The grain boundary diffusion is a complicated process.
Heat treatment could reduce the number of pores in the Al spray coatings. 3.
Grain boundary diffusion of atoms occurred in various engineering materials at elevated temperatures.

The microstructure of this ceramic material is constituted by large elongated β-Si3N4 grains with high aspect ratio embedded into a matrix of smaller grain size.
The plane A is constituted by numerous large elongated grains, promoted by the seeding, embedded into a Si3N4 matrix of smaller grain size (Fig. 1a).
Those elongated grains are mostly oriented with their lengths parallel to the extruding axis.
a 20 µm b 20 µm intensities of those peaks, (200):(002), can give an estimation of the degree of texture of the material, comparing it to the reference value calculated from the β-Si3N4 diffraction card (pattern number 33-1160) that is 6.7.
While the ratio for the surface A is 10.4, which indicates a higher number of elongated grains than in a standard Si3N4 material, the value calculated for sample C is one order of magnitude lower (ratio of 1.3).