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Grain growth is hardly possible in the case of rapid local heating during mechanical milling.
Since a considerable number of compounds undergo incongruent melting, it is of great interest to study these compounds with respect to their melting behavior.
The peritectic melting temperature was reduced more than 100 K for FeSn2 grains of about 40 nm in size (r ≈ 20nm).
However, grain growth during slow heating in DSC prevents such a large reduction of the peritectic melting temperature.
Substantial grain growth due to local melting is rather unlikely during mechanical milling.

The amorphous phase devitrifies by the formation of a large number of nuclei of crystallization that exhibit slow growth at this temperature (Fig 3a).
The electron micrographs exhibit fine grains, 20–70 nm in size.
Structure and grain size of titanium nickelide subjected to deformation and subsequent heating Treatment conditions Structure Grain size, [nm] Number of anvil 1/4 Deformed 10–45 revolutions upon 1 Nanocrystalline + amorphous 7–25 deformation 5 Amorphous + rare isolated grains 3–5 10 Amorphous + rare isolated grains 3–5 Heating temperature, 200 Amorphous + rare isolated grains 3 -–5 [°C] 300 Amorphous + isolated grains 5–20 200 + 250 + 300 Amorphous + nanocrystalline 5–20 300 + 350 Nanocrystalline 20–70 It is seen that the crystallization of the amorphous alloy upon heating to 300°C is sluggish, whereas after heating to 350°C, a "jump-like" development and completion of crystallization takes place.
The grain size varies over a wide range but remains less than 100 nm.
The size of formed grains varies from 20 to 70 nm.

Sku Evaluation of the contours of abrasive grains: The larger the Sku value, the more concentrated the abrasive grain height distribution.
Besides, the delta-like binder residue exists behind the abrasive grains.
Table 7 The 3D roughness of diamond grinding wheel obtained by different truing method Experiment number Grinding wheel status Sp (μm) Sq (μm) Ssk Sku 1 Grinding wheel being wear 23.23 5.34 -0.97 5.47 2 Diamond roller truing 27.07 5.60 -0.69 5.56 3 GC cup truing 38.22 6.51 -0.56 7.04 From the data in Table 7, it is concluded that after the wheel being wear, the grains are abrasive and the abrasive grains fall off, resulting in a significant increase in the absolute value of Rsk.
(a) Grinding wheel being wear (b) After diamond roller truing (c)After GC cup truing Fig.5 The three-dimensional topography screenshots of 600 # diamond grinding wheel in different state It can be seen from Fig.5, the surface of the new grinding wheel and grinding wheel being wear almost have no abrasive grain, but after diamond roller truing, the grinding wheel surface show less abrasive grain, while a great number of abrasive particles is obtained after GC cup truing.
In this paper, we have further verified the truing mechanism of GC cup grinding method: GC abrasive grains have abrasive impact on abrasive grains and binder of diamond grinding wheel, and the bonding agent of front and side of diamond abrasive was cut off by GC truer, and the abrasive grain behind the agent survived due to the protection of abrasive grains.

The research results show that the grains of Cu-15Ni-10Mn alloy as-cast can be refined by tiny amount of Ti.
According to the Hall-Petch formula () [5], the smaller the grain size of alloy, the better plastic deformation ability.
Therefore the processing feature can been inclined by decreasing the grain size.
With the increase of the amount of Ti, the number of grains rises, and the refinement degree also increases obviously.
Ti has a high melting point, and acts as nucleation particles during solidification, that destroys the original interface and forms a large number of particles, and become the new crystal nucleus of crystal that makes the alloy grain refinement.

As shown in a number of studies, interfaces in the in situ Cu-Nb composites are semi-coherent and partly amorphous [5,6], whereas the impact of texture on strengthening and deformation mechanisms was revealed in [7-11].
Microhardness of Cu-Nb composite versus the number of revolutions of HPT Under the HPT by 1 revolution the structure obtained is not homogeneous.
The grains of Nb are round-shaped and embedded in the polyhedral Cu matrix.
The third stage corresponds to the growth of recrystallized grains.
Under the HPT the ribbon-like shape disappears and nearly equiaxed Nb grains are formed, refining to 10-20 nm.

A large number of magnetic grains attracted on N and S magnetic poles arrange in brush-shape along the magnetic line of force.
The brush formed by magnetic grains is called “magnetic-brush”.
In Fig.1, at point A, the force condition of a magnetic grain in a three dimensional magnetic field is shown as follows: x H xHVF 0x � � = v  ˈ y H yHVF 0y � � = v  ˈ z H zHVF 0z � � = v  ˈ zyx FFFF vvvv ˇ + = . (1) Journal Title and Volume Number (to be inserted by the publisher) 637 where, V0 is volume of magnetic grain, (m3); x is magnetic susceptibility of magnetic grain; H is magnetic density, (A/m); z H y H x H � � � � � � ,, are the differential of magnetic density along x, y and z directions, respectively.
For the pole Ⅰ: n=408 r/min; � =3 mm; the magnetic density in the clearance, 0.5 T; size of the magnetic grains, 60 #; dose of the grains, 10g.
For the pole Ⅰ: n=649 r/min; � =5 mm; the magnetic density in the clearance, 0.9 T; size of the magnetic grains, 60 #; dose of the grains, 15g.

Residual film stress may result in a lower mechanical reliability of the film arising from a number of failure mechanisms, such as film splitting and spallation.
The grain sizes are becoming bigger from (a) to (b), and to (c).
The film presents already faceted polycrystalline grains of 20-60μm in sizes.
Fig.3 shows the waviness profile of grain sizes.
Therefore, a large number of spectra were recorded from a selected area and added (summation method).

Two sets of experiments were done accounting for a total of 18 numbers of experiments.
The grain size in that area is found to be in the range of 5-6 microns.
The fracture area is seen at the left side of the microstructure with fine uniform grains and plastically deformed grains.
Grain size at the nugget zone is in the range of 2 to 4 microns.
The added SiC particles in the weld region had retarded the grains from grain coarsening in the annealed samples.

The β phase precipitates as a discontinuouslatticeat the grain boundary.
After the first pass, although the coarse grains are still visible, a grain refinement may be noticed.
Along with a greater reduction in grain size, in the second and third pass an elongation of large grains in the extrusion direction can be seen.
The grain refinement of the ZK60 alloy is caused by dynamic recrystallization of the material during deformation and static recrystallization which may occur between passes After the fifth and sixth passes it can be seen that the grains are elongated and the grain size increases.
After processing through ECAP route A the microstructure of ZK60 shows that the grains are refined with the increasing number of ECAP passes.The XRD analysis identified the same peaks as the ones encountered in the as-received material, which present a reduced intensity with the increase in strain.

In the PLD method, the duration of film deposition is controlled by a number of pulses.
In the experiment the number of pulses varied in the range from 10000 to 55000.
Dependence of surface roughness, grain density, and grain area on thickness is shown on Fig. 1.
Fig. 1 – Dependence of grain parameters of nanocrystalline VOx films on thickness The results show the characteristic curve of grain area depending on films thickness.
The area of the grain boundaries (areas of conductivity) and the concentration of charge carriers increase with increasing grain density (i.e. the number of grains per unit area).