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It was established that upon SPD a number and a size of aluminides decrease with increasing a degree of deformation.
The number of anvil revolutions was varied from 0.5 to 10 (equivalent to logarithmic true train e = 3.8-6.7).
The matrix phase has grains with size about 5 µm.
Matrix lattice parameter and the relative level of matrix microstresses (a) and the hardness (b) of the Al-2% Fe alloy depending on the number of revolutions It was show that upon annealing at temperatures below 250 o C (for Al-Zr alloy) and 300o C (for AlFe and Al-Cr alloys) the grains do not grow above 300 nm.
The most intense grain growth begins at temperatures above 350 oC and 450 o C the grain size reaches 1.5 µm.

Note that the peak intensity of the γ-Fe phase increases with the number of pulses, indicating that the volume fraction and/or grain sizes of the γ-phase increases with increasing the number of pulses.
As shown in Fig. 3(a) , very fine grains with sizes of 100 nm approximately are homogeneously dispersed on the whole irradiated surface, clearly indicating that the melted surface layer are mainly composed of refined grains or subgrains.
It is worth noting that the interiors of fine grain appear to be clean without any detectable defects.
They are often present at the grain boundaries and triple junctions.
Figure 4 Surface microhardness of samples with different pulse number after HCPEB irradiation Figure 4 shows the microhardness changes of 3Cr13 steel before and after HCPEB treatment.

Strain of Grains.
The total number of grains used for the measurement was about 240.
Grain Rotation in Oyz-plane.
Grain rotation is mainly produced by inhomogeneous deformation around a grain.
Fig. 15(a) shows measuring principle of strain inside a grain, where the measuring position is shown with the grain number 2 in Fig. 13.

A number of electrodeposited alloys are of interest due to various properties.
At low temperature, the grain is decreased and the grains began to adhere and grew together.
A greater number of grain boundaries with the highest proportion of atoms inside the boundaries created an extremely high volume fraction of grain boundaries in the CoNiFe microstructure [9,10].
At higher temperatures (>700oC), the coating began to soften as the grains conglomerated and reducing the number of hardening sites.
The grain size reduction has resulted in the high volume fraction of the boundary atoms inside the grain boundaries.

With biaxial deformation, grain boundary slide occurred more frequently than with uniaxial deformation, causing grain boundary separation and formation of micro-voids between the grains.
In the vicinity of the cracks and at the locations of grain boundary separation, although deformation temperature at higher than the recrystallization temperature, fine grains (about 2 µm) showing in duplex grain structures were formed locally.
Otherwise, mechanism of fine-grained superplastic diffusion bonding mainly depends on grain boundary sliding and grain rotation by adjustment of void diffusion and dislocation motion, and going with obvious atom diffusion.
That results in the migration of different number of atoms in the twoides of interface.
Microhole is difficult to avoid, but its number and size is less than those of mechanical joining area.

Grains shape and array model 1.
Computational model of CHTC (hf) based on “grain state”.
The Reynolds number, Re, and the Prandtl number, Pr can be determined by Eq. (11) and Eq. (12)
Based on the simulation tangential grinding force of single grain, and from Eq. (22) and (23) [11], we can conclude the simulation tangential grinding force of more grains with the grain grit 70#, shown in Table 4
(22) Where Fts andFtm are the simulation tangential grinding force of single grain and more grains respectively, and Nt is the active number of grains per unit area, expressed as Eq. (28) [11]

A large number of intragranular pores and a small number of overall pores was observed in Ca-PSZ, resulting in this material having the lowest bulk density.
The grain size of Ca-PSZ is non-uniform, and most of the grains, those with an average grain diameter of around 6 μm, are densely packed, however, there are also some irregular grains, with an average grain diameter of around 10 μm, and a large number of pores, resulting in the low bulk density of the material.
The average grain size of Mg-PSZ is larger, with an average grain diameter of around 7 μm, and the grain shape is irregular.
Y-PSZ has a uniform grain size, with an average grain diameter of around 5 μm, and sharp edges.
No abnormal grain growth was observed for the sample, the grain bonding is compact, and a small number of pores exist in the material.

The heat added to the metal causes grains to grow by absorbing smaller grains.
Grain Size, Microstructure and Surface Finish.
The grains in the HT+SR are much smaller and finer than the untreated sample grains, while the SAA grains are much larger and coarser in comparison to the untreated sample grains.
Table 3 shows the grain numbers and size gathered from each of the samples.
HT+SR Untreated SAA SR Sample ASTM Grain number Grain Size (um) No heat treatment 5.73 54.9 Stress relieved (SR) 5.42 49.3 Age hardened (HT+SR) 6.25 40.9 Fig. 2. 5x magnification micrographs of samples Table 3.

Composites under study (N is the number of Nb filaments).
They were identified according to the EDPs as intermetallic Ti6Sn5 particles, but on the whole the number of these particles in Samples 1 and 2 is negligible.
In Fig. 4c a remarkable grain size scatter is observed, fine grains neighboring with much coarser ones.
Compared to the previous samples, a greater number of second-phase particles are observed (indicated with arrows in Fig. 4c).
The number of these particles is not very great and not enough for the pinning force enhancement, but Nb3Sn grains in the vicinity of these particles grow coarser.

Grain size of NiO and SDC could be estimated from the diffraction peaks according to Scherrer equation expressed as[5]:
Table 1 Cell parameter and grain size of NiO and SDC Sample Cell parameters Volume Average grain size A(×10-1nm) V(×10-3nm3) D(nm) NiO SDC NiO SDC NiO SDC NiO400-SDC400 3.965 5.427 62.4 159.9 30.1 15.6 NiO600-SDC600 3.969 5.428 62.6 160.0 56.5 19.7 NiO800-SDC800 3.969 5.430 62.6 160.1 63.4 44.8 The grain size of NiO powders calcined at 400, 600 and 800℃ is 30.1, 56.5 and 63.4nm, and the size of SDC is 15.6, 19.7 and 44.8 nm.
As shown in Table 1, there is grain growth with calcining temperatures from XRD lines broadening.
Thus, the high performance of this anode seems to be attributable to the increase in the number of active sites at the boundary between Ni, SDC and H2 gas.
As shown schematically, the Ni grains form a skeleton with well-connected SDC grains finely distributed over the Ni grains surfaces.