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Results and discussion Effect of the substrate on surface morphology and grain size.
As can be seen in Fig.1, comparing with substrate for T4-CA material, crystalline grains of substrate for T2.5-BA material are larger and coarser, and low-density grain boundaries.
For CA material and the secondary cold rolling for CA, DR-8CA the grain of an even smaller grains along the rolling direction of the extension of the trend of a higher density of grain boundaries, which was mainly due to use of secondary cold rolling processes, reduction ratio of 20% ~ 40%, resulting in a number of grains have been extended, and even crushed [3-4]. ①T4-CA ②DR-8CA ③T2.5-BA ④DR-8BA ② 50μm ④ 50μm ① 50μm ③ 50μm Fig.1 Metallographic structure of TFS black sheet ① ② ③ ④ Fig.2 Surface morphology of the TFS products under different annealing/rolling modes The surface morphology of TFS products is observed by SEM corresponding to metallographic structure for T4-CA, DR8-CA, T2.5-BA, DR8-BA, as shown in Figure 2.
Grain size of TFS products surface for BA is more coarse, dense, and less porous.
This was mainly because that the different modes of annealing and rolling affect the surface of the substrate grain size, which led to significant differences in the grain boundary.

Introduction The current interest for the production of fine grained materials by severe plastic deformation (SPD), leads to a large number of investigations focusing on the substructure development and the related mechanical properties.
Both materials were received in as cast condition with an initial grain size of ∼250 µm.
For alloy AA5182Cu these numbers are after 4 ECAP passes 24% HAB and an average (sub)grain size of 2.3µm, and after 8 ECAP passes 42% HAB and 1.4µm (sub)grain size.
� Grain refinement in alloy AA5182+Cu during ECAP, is delayed compared to alloy AA5182
The authors are also grateful for the financial support provided by the Belgian Science Foundation (FWO) under contract number G.0208.02.

The rate of annihilation is determined as the change in the number of dislocations of the same sign N depending on time: .
Pearlite grains (about 30%) consist of cementite and ferrite interlayers.
This can be explained, taking into account that the microhardness of pearlite grains is about a third higher than that of ferrite grains.
Using a model crystal with a size of 1000 b, the dependencies in the variation of the number of dislocations and strain in a pile-up on time were analyzed.
Rybin, Grain Boundaries in Metals, Metallurgy, Moscow, 1980.

In the role of the main characteristics that define the operation of magnetron coatings were adopted: the coating microhardness Hμ, grain size d, wear resistance I.
(1) Where S - discharge rate (the number of atoms ejected by one ion); Δm - mass loss of spray material, mcg; j - ion current (mA); τ - time (h); K - coefficient depending on the choice of units; A - mass number of the atoms.
Influence of technological factors on microhardness: discharge power and grain size in magnetron sputtering TiNi - (a); discharge power and pressure in the chamber - b); discharge current and grain size - c); dependence of durability: the discharge power and microhardness - d) The remaining process parameters were assumed constant based on published data and experience.
Posed a series of experiments planned on the basis of plans uniforms-rotatable second order allowed with a minimum number of experiments to make a statistical model magnetron sputtering process alloys with shape memory 321H steel thickness up to 3 mm.
(5) Where Нμ - coating hardness, GPa; I - wear resistance in mg/m; N - discharge power, kW; d - grain size, nm; I - discharge current, A.

Fig.2. a) 20x photos of the layers on the bearing end: (1) babbit lining Cerrox (babbit); (2) copper-based material (copper); (3) interlayer chamfer; (4) steel shell; (5) chamfer of the outer side of the shell; (6) the drill. b) Samples of abrasive cloths in 200x blowup: (1) AC80, 0.2 mm grain; (2) AC150, 0.1 mm grain; (3) AC230, 0.055 mm grain; (4) AC320, 0.045 mm grain; (5) AC600, 0.025 mm grain; (6) an abrasive cloth glued to the shaft.
Figures 1…7 correspond to the numbers of formulas (1) … (7) in Table 1.
Deviation of MSVs in dependence to abrasive grain sizes AC on the Fig. 4 proves this conclusion.
The lowest values of WI are typical for AC600 with the grain size of 0.025, and the highest values occur in the case of AC80 the grain size amounting to 0.2.
Features of Wear of Abrasive Grains Depending on Microcutting Speed of Steels.

The results showed that the nano-WO3 particles were mainly distributed in the grain boundary of Cu2SnSe3 matrix, and the grain growth of Cu2SnSe3 was inhibited.
It can be observed that the grain size distribution of Cu2SnSe3 matrix phase is about 3 um, and the grain boundary is clearly visible after sintering, showing that the particles have a perfect binding.
Fig. 2(c)-(f) shows the nano-WO3 particles are mainly distributed on the grain boundaries and with the grain size of the matrix is obviously smaller the increasing of nano-WO3.
The introduction of nano-WO3 produced a large number of defects within the crystal, therefore increasing the phonon scattering at the grain boundary.
Nano-WO3 particles were mainly distributed in the grain boundary of Cu2SnSe3 matrix, and the grain growth was inhibited.

It's shown that the grain size and overall amount of carbide phase has almost no effect on ICC.
n,  - number and reduction at TMP correspondingly; D - grain size;  - dislocation density; o - density of precipitates evaluated by the light microscope measurements; e - density of dispersed precipitates evaluated by TEM; F - fraction of fragmented volume; R - fraction of recrystallized volume.
It should be noted that in the substructure of steel worked with a reduction up to 30% and n=3 the structure becomes more perfect in compare with single-pass rolling, the grain boundaries and solid solution are improved as a result of dynamic strain aging and dispersed precipitation of titanium carbide distributed comparatively uniformly throughout the volume of grains.
In contrast to data obtained in [9] for a similar steel given TMP, the grain size and overall amount of carbide phase in this case has almost no effect on ICC.
Billets differing in average grain size (by factor of two) have almost the same corrosion rate.

The high angle of misorientation between a and b grains can be attained already after a single ECAP pass.
Another method of SPD applied to refine a grain structure was accumulative roll-bonding (ARB) process, carried out in the 70/30 brass alloy sheet on up to six cycles to obtain nano-grains [3].
After six cycles, texture intensity reduces slightly, which can be explained by nano-grain formation.
No grain refinement can be seen, only growth of dislocation density and a single twin can be observed.
The microstructure studies show that the dislocation density is relatively high after both modes of deformation, while after additional groove pressing increases number of deformation twins and fraction of high angle grain boundaries and decreases grain size.

Note that type K - damage refers to cases with little damage outside the main lines of damage; type C damage refers to cases with distributed cavity formations; - at low levels of orientated cavitation (class 3a lower limit) types K and C may be inseparable; - cavity chain = formation with several cavities on a grain boundary extending to adjacent grains - GB = grain boundary 3.
NORDTEST NT TR 302 thus specifies the number of cavities in more detail, especially in damage classes 3 and 4, which makes evaluation of creep cavitation damage more independent on the subjective visual observation and evaluation.
Cavities were found at grain boundaries and also at the inclusion-matrix interface, where it was not possible to exactly confirm or deny their presence by OM.
On the other hand, coarse grained part of heat affected zone (CG HAZ) was heated up to temperatures well above Ac3 and microstructure completely transformed during welding.
At the same time, significant inhomogeneity of cavitation damage was confirmed again, when the number of cavities decreases with increasing distance from the outer surface of the pipe.

The experiments were carried using Taguchi optimization method, which studies a large number of variables with a small number of experiments.
The piezoelectric effect is averaged over all grains.
The substrate material also determines the sputtered grain size.
The proportionality of the gas mixture also controls the grain size of the piezoelectric material, when the ratio of Ar/O2 increases, the grain size also increases[14].
This will allow simultaneous evaluation of several parameters such as gas pressure, deposition time and RF power using a series number of trials.