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Under intense plastic deformation at elevated temperatures, the interstitial impurity concentration on and near the grain boundaries can vary, which naturally affects the ability of the grain boundaries to generate dislocations and also affects the resistance to motion of dislocations near the boundaries and inside the grains.
As a result of this pressing regime, a submicrocrystalline structure with average diameter of the elements of the grain–subgrain structure equal to 310 nm was formed for an initial (before pressing) grain size of 10 μm [2] Here the elements of the grain–subgrain structure have a preferentially equiaxial shape, and the fraction of large-angle grain boundaries stands at about 70%.
For both the submicrocrystalline structure and the coarse-grained structure, fracture is ductile.
In addition, pores are observed on the fracture surface whose diameter is less for the submicrocrystalline structure, and their number greater, than for the coarse-grained structure.
In particular, these can be grain-boundary sliding and vacancy creep.

The purpose of the research is to determine the effect of a mixture of water of different structure on the strength of fine-grained concrete and the speed of its formation.
However, the availability of such cements "on hand" in a significant number of cases is significantly limited and requires a solution to the problem of organizing their search and transportation in sufficient quantities.
The problem lies in the clearly insufficient number of existing methods of calculation, construction and organizational and technological measures to ensure the stability of concrete.
Aim of Paper The purpose of the research is to determine the effect of thermally activated water on the strength of fine-grained concrete and the rate of formation of its structure.
Shishkin, Research into effect of complex nanomodifiers on the strength of fine-grained concrete.

Electrodeposition has a number of advantages compared to other processes of producing thin nanocrystalline films, including the possibility of deposition of a large number of pure metals, alloys and composite materials with grain sizes less than 100 nm with no restriction on the shape and surface area for deposition, high performance, low cost and easy transfer of technology from the laboratory to mass production [5].
Nickel is a ferromagnet, which has been successfully electrodeposited on metal and semiconductor substrates with a grain size in the nanometer range.
In recent years there has been a large number of studies on the physical properties of nickel films and knowledge has been gained about the relationship of their structural, magnetic, electrical and mechanical properties [6-12].
As a result, it was found that the average grain size for all the films was 19.81 nm regardless of the film thickness.
[16] Herzer G., Grain size dependence of coercivity and permeabilityin nanocrystalline ferromagnets, IEEE Trans.

Most of the matrix was found to be composed of fully recrystallized grains with average diameters around 10 microns.
Zones characterized by finer submicron scale grains could also be identified locally as well as grains containing networks of subgrain boundaries.
In their work they consider that the stability of carbides in steels decreases with the increasing element group number.
When measuring grain/particle sizes with EBSD [5] a grain/particle is defined by the minimum number of data points per grain, the threshold boundary misorientation angle and the step size.
Humphreys has shown that a minimum of 8 pixels per grain are required for an accuracy of 5% in determining the grain size [5] The results shown in figure 5 b) indicate that the VC particles are submicron sized with an average particle size of ~400nm.

Grains reveal higher hardness, strength and regularity with comparison to Al2O3 grains (corundum).
Fig. 1 Wear of abrasive grains, a) Al2O3 grain prior to use, b) the grain Al2O3 after use, c) the grain SG prior to use, d) SG grain after application Abrasive grain is so tenacious that in order to prevent the occurrence of excessive forces during grinding it is mixed with conventionally fused corundum grains at the grinding wheel production.
Fig. 2 TG 2 abrasive grains [6] The further SG grains development mainly focuses on the production of new forms of grains.
Applying the load to grains a conchoidal fracture occurs and thereby increasing of number and sharpness of the cutting edges.
The grain has self-sharpening properties of ceramics grains but with a slower course [5].

The scanning electron micrograph results reveal different grain shapes and sizes and also different grain growth rate during welding.
The first group of EWP-D and EWP-H contains round and equiaxed grains.
It can be seen that the grains at the balled region are very large, i.e. in EWP-E electrode, the cross-section is almost consumed by one very large grain.
The ability to control the grain growth rate and keep grain size small especially within the balled end is crucial in determining the quality in term of the endurance of the tungsten electrode used.
Acknowledgments The author would like to thank National Metal and Materials Technology Center (MTEC), Thailand for financial support (project number P1550713), equipment and facility used in this research.

There are only a few dynamic effective grains and a large number of redundant grits, which can not only increase the cost of the tool and a waste of abrasive resources, but also will cause a high grinding temperature and make the inclusive chip space of the grinding wheel decreasing.
According to the theory above, each grain on the surface of the grinding wheel can be seen as a seed, with the method of photolithography and electroplating, and using UV photosensitive dry film as a mask layer, an electroplating grinding wheel with abrasive phyllotactic configurations can be made [5].Then using same method, the grinding wheels with other configuration were also done, and the grain number per unit on the grinding wheel surface keeps the same amount.
CBN abrasive size is 70/80 Mesh and the abrasive grain number per unit is 129.69/cm2.
(a) Photograph (b) Schematic diagram Fig 2 The experimental setup of grinding Experimental results and analysis As is shown in the Fig.3, for electroplating CBN grinding wheel, as the workpiece materials are removed by the grains, the abrasive grains are worn, the number of effective abrasive grains in the contact arc length of the grinding wheel will increase and reach a steady state, which make the grinding force is increasing and tends to be stable.
Fig 6 The influence of the depth of cut on the grinding force For ordering grinding wheel, the grain number of cutting material are increased and the grain number of rubbing and ploughing material are decreased in grinding contact region since the abrasive grains are reasonably arranged on the surface of the grinding wheel.

In the region of coarse grained HAZ granular bainite with large grain size can be found as shown in fig.5b, and rod-like and dot-like martensite/austenite constituents distribute on the matrix.
Because of coarse grain size and a number of martensite/austenite constituents, this region always performs local brittle behavior [1].
Weld metal Coarse grained HAZ Fine grained HAZ Hardness(GPa) 3.85 4.11 3.8 Elastic modulus (GPa) 205.8 210.3 201.2 (a) Weld metal (b) Coarse grained HAZ (c) Fine grained HAZ Fig. 3 Typical load-displacement curves of different regions in the welded joint It can be seen that the minimum indentation depth is located in the coarse grained HAZ and the indentation depth between in weld metal and in fine grained HAZ is almost equal value, which indicates that the different hardness behaviors exist in different regions.
According to table 1 the average hardness is as follows: fine grained HAZ＜weld metal＜coarse grained HAZ.
It can be seen that the average value of E is 205.8 GPa, 210.3 GPa and 201.2 GPa in the weld metal, coarse grained HAZ and fine grained HAZ respectively.

Furthermore, grain refinement occurred due to dynamic recrystallization.
It was found that the number of Al2Ca was much larger than that of Al-Mn-based IMCs, indicating that the dark areas observed in Fig. 1 consisted mainly of Al2Ca.
Figure 4 shows the microstructure in the SZ, consisting of fine equiaxed grains whose average grain size is 5.6 μm.
Furthermore, the number of Al2Ca was less in the FSPed specimen than in the as-extruded one as seen in Figs. 1 and 4.
In general, the hardness increases with decreasing grain size, namely strengthening effect of grain refinement.

mm ≥ 549 – ≥ 35 196÷343 ≥ 5 stable Furnace heating, average values for pipes Dp x Sp = 16х1.5 mm 642.7 – 46.1 247.2 10.8 stable * Note: number of single grains is specified in brackets 100 мкм 100 мкм 100 мкм 100 мкм 100 мкм 100 мкм 100 мкм 100 мкм Fig. 2.
Microstructure of metal of the pipes after treating: a – I = 420 А, U = 58 В, grain size 10 and 9 points and deformed non-recrystallized grains, = 679 MPa, = 434 MPa, = 37.2%, = 368 MPa; b – I = 430 А, U = 60 В, grain size 10 and 9 points and deformed non-recrystallized grains, = 703 MPa, = 472 MPa, = 32.4%, = 296 MPa; c – I = 500 А, U = 70 В, grain size 10 and 8, = 603 MPa, = 282 MPa, = 51.8%, = 204 MPa; d – I = 550 А, U = 75 В, grain size 10(7) and 8, = 597 MPa, = 274.4 MPa, = 53%, = 191 MPa; e – I = 600 А, U = 77 В, grain size 10 and 9, = 604 MPa, = 243 MPa, = 53.9%, = 149 MPa; f – microstructure of metal of pipes after furnace heating, grain size 10 and 8, = 637 MPa, = 358 MPa, = 51.5%, = 304 MPa; g – I = 760 А, U = 105 В, grain size 5 and 6(7), = 580 MPa, = 220 MPa, = 60%, = 181 MPa; h – I = 800 А, U = 105 В, grain size 4 and 6, = 553 MPa, = 206 MPa, = 64%, = 144 MPa.
It should be noted that at the heating mode with a current of 500A, rather big number of sections (about 30-40%) with grain size smaller than 10 points is observed in a microstructure of metal (Fig. 2c); that confirms underheating of pipes in the course of heat treatment.
The microstructure of metal of heat treated at current 550A and 600A consists of austenitic grains of 10,8 points and single grains of the 7 points (Fig. 2d and 2e), which size is rather far from admissible limit (not larger than the 5 points).
In a microstructure of metal of pipes heated at the current of 650A, 6 points grains which size is close to maximum permissible 5 points are observed besides austenitic grains of 8,7 points.