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The grain diameters are given in Table 1.
The results showed that the Nb and/or Mo addition to FeCuSiB alloys inhibit the grain growth and the average grain diameter was almost the same for these samples.
Table 1- Grain diameter for the nanocrystalline samples.
The beneficial effect of Mo on the corrosion resistance of iron based alloys may be interpreted in terms of reducing the number of active sites by forming a uniform passive layer.
It was also suggested that the Mo could promote the formation of more uniform passive layer diminishing the number of active sites.

Grain size was determined using a linear intercept method from a large number of overlapping measurements.
From Fig.1, we can find that the equiaxed grain with the area fraction of 95% composed the majority of grains.
The equiaxed grain size is 17 μm and does not change during aging.
Fig. 5 gives the dependence of area fraction of twinned grain and twin on aging time at a plastic strain of 4 %.
These results are in contradiction with the previous report [13] that the increase of SRS with a decrease in quasi-static flow stress observed in a number of steels and aluminum alloys.

Here, one of the modern methods of protection against material destruction is the application of heat-resistant coatings by plasma spraying, which includes a number of operations [3,4,5], for surface preparation, applying a sublayer (if necessary) and a heat-resistant coating, and in some cases electroablation and subsequent heat treatment.
After testing, three types of granules of different granularity were selected: black silicon carbide grade 54C with a grain of F20; F46 and white electrocorundum with a grain of F30.
When processing particles of a larger fraction, the number of such defects increases, their size and length increases (this section is highlighted in fig. 3, b) a) b) Fig. 3.
Micro-Surface of the sample with a mineral-ceramic coating a - after sandblasting with grain SIC fraction F46 b - after sandblasting grain SIC fraction F20 The cross sections shown in Fig. 3, a, are obtained by sandblasting with silicon carbide with a small particle size (fraction F46).On these samples, the intermediate layer has a uniform sublayer thickness across the entire plume.
The use of coarse grain allows you to speed up the coating process, but requires further processing, which reduces the thickness of the coating and its thermal protection properties.

And the surging force can be calculated from Eq.1 [8]: 2 2 sin 2 1 ;0 cos 2 m p d M fT A B F F T a tN f ω π + + = ≤ ≤ ∆ (1) Where M is the equivalent mass of vibration parts; f is the ultrasonic frequency; T is the contacting moment of abrasive grain and workpiece; A, B is amplitude in X, Y directions. a is the cone vertex angle; t∆ is the contact time; dN is the dynamic effective particle number; mF is the friction between abrasive grain and workpiece.
When the abrasive grain contact with workpiece the force appear, and when the abrasive grain separate with workpiece the force disappear.
The grinding process can be deemed as indentation between abrasive grain and workpiece.
When abrasive grain was pressed into the workpiece, plastic deformation will generate around the contact area, as shown in Fig.2a.
At the same time, when 0θ= , namely in the indentation direction of the abrasive grain, θθσ will increase with the loading of the abrasive grain, and when it reaches the fracture limit, median crack will occur, as shown in Fig.2c.

At the first stage, the specimens numbered 02 and 15 were irradiated up to the fluence of 4x1015 ions/сm2 (Е=130 MeV) while the specimens numbered 05 and 09 were irradiated up to the fluence of 1x1015 ions/сm2.
The comparison with Fig. 5a where grain structures are depicted reveals that the density of blisters varies in different grains – the defect density in some crystals is relatively low, while in others it is substantially higher.
The order distributing feature is that αʹ martensite appears in the grains which are predominantly (001) oriented and nucleates mainly at the grain boundaries.
At the same time, ε-martensite (hcp) nucleates in the grains which are (111) oriented.
The ε – martensite was located inside the (111) oriented grains.

The DDWs are present only in smaller grains and not in coarse grains, as shown in Fig. 1b.
These substructures allow a faster recovery and nucleation at the vicinity of the grain boundaries of the smaller grains.
In the early stages of recrystallization a large number of new grains are formed in the smaller grains and some new grains are formed in transition bands.
The subsequent recrystallization starts firstly from the smaller grains and the transition bands inside coarse grains.
It finishes with the growth of new grains by consuming the remaining deformed zone inside coarse grains.

During the grinding process the main role is played by the vibrating phenomena caused by primary imbalance of a wheel, features of its structure, and also the existence of a component arising in the general scale of vibrations and caused by the change of the structure of a working surface of a grinding wheel, wear of its working abrasive grains during the process.
The variable component takes into account the impact of the intensity and extent of wear of abrasive grains, associated with the appearance and subsequent growth of contact pads of the working abrasive grains wear.
During the process of grinding the above frequencies – 22.5, 220, 400, 600 and 800 Hz are preserved, however, between 600 and 800 Hz there is a new frequency range which arises as a result of the interaction between the grinding wheel (individual abrasive grains) with machined piece, its blunting and change of the initial relief work surface (fig. 2, b).
The nature of changes of vibration dynamic processes has a number of common features by changing the status of contacting surfaces.

And alloys 1 and 2 contained dispersed phase α-Zr which can lead to grain refinement.
It can be concluded that I phase precipitates gradually from W phase with reducing of temperature, and there are still a large number of W phase at room temperature, so that affecting greatly the final content of I phase.
And it should be noticed that when the temperature of Alloy 2 is lower than 150 oC, a large number of Z phases will be precipitated from I phase, which reduces the strengthening effect of I phase.
Zr element can refine the grain size and improve the structure and properties of Mg alloys.
Mukai, Ultra-fine grain size and isotropic very high strength by direct extrusion of chill-cast Mg-Zn-Y alloys containing quasicrystal phase[J].

RAC was defined as the local reduction of area where a pore number density of 1mm-3 is exceeded.
The pore number density as a function of local RA was calculated based on the moving average of the number of pores' gravity centres within a volume of 0.25mm width along the tensile direction.
Consequently, transverse growth of existing cracks and pores is impeded by formation of a fine-grained microstructure and excellent grain boundary mobility.
Thus, the numbers suggested are to be considered only as a rough guideline.
However, to the authors' knowledge, no indication of Ni strongly affecting austenite grain boundary mobility is reported in literature.

(6) is the geometric constant (~16), the grain boundary diffusivity, the grain boundary width, the volume of a diffusing atom and the Boltsman’s constant.
P is the total number of sub-layers in the FG layer.
FG TBCs with n of 0.25 show the highest value of maximum in-plane tensile stresses in ceramic phases in case of the grain size of 1 mm, while the lowest value in case of the grain sizes of 10 and 40 mm.
The modes of critical stresses in ceramic phasesdeterminingcriterion of fracture of FG TBCs are out-of-plane stresses in case of a grain size of ZrO2 of 1mm, while in-plane stresses in case of grain sizes of ZrO2of 10 and 40 mm, which means that in case of a grain size of ZrO2 of 1mm vertical cracks propagate in the FG TBC thickness direction by the in-plane stresses, while in case of grain sizes of ZrO2 of 10 and 40 mm, horizontal cracks propagate in the in-plane direction by out-of-plane stresses.
For Case III, the modes of critical stresses in ceramic phase determining fracture of FG TBCs are out-of-plane stresses in case of a grain size of ZrO2 of 1mm, while in-plane stresses in case of the grain sizes of ZrO2 of 10 and 40 mm.