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It can be seen that the number of cleavage planes of Alloy Ⅰ is higher than Alloy Ⅱ.
However, the number of dimples shows the opposite trend.
The curves of crack length versus the number of cycles (a-N curves) are presented in Fig. 3(b).
It can be seen from Fig. 5(a, c) that fine recrystallized grains ( the green part in the picture ) are scattered in the alloy and the number is small.
In general, the FCP rate is smaller for alloys with coarse grain size than for those with fine grain size.

Microstructural parameters covered included the morphologies of martensite, the sizes of the prior austenite grains, grain sizes and grain boundary misorientations, and the number density and size of precipitates.
Results and Discussion Number density, size and chemical compositions of NMIs.
The total number of NMIs decreased by 7% as a result of ESR.
The number of NMIs per mm2 in all size ranges decreased as a result of ESR except the number of NMIs per mm2 in the size range 6-10 µm which remains unchanged.
Using Image J software, the numbers and sizes of all precipitates were calculated.

The grain body was characterized by a sufficiently large number of twins of annealing and precipitates of Cu2O oxide in the form of dark gray inclusions of various sizes (from 0.3 to 5 μm) and shapes (mostly round and elongated) having a regular orientation along the rod axis and a stringer-type arrangement (Fig. 1 a).
Almost equiaxed grains are observed in the microstructure of the transverse section of the wire.
The following assumptions were made: the samples were considered as pure copper with a certain grain size.
EBSD Analysis of the Submicron Width Fibber Shaped Grain Copper Fabricated by Drawing, Mater.
Determination of grain size.

The methods of local form-shaping of the parts under SP [5] conditions allow to solve the problem of fabrication of the complicated axisymmetric parts provided a minimum metal loss, without application of powerful press equipment and massive forging tools and with minimum number of operations.
In this case the main mechanism of deformation is grain boundary sliding.
Therefore, in the rim of the disk it is important to have coarse-grained structure that give the material heat-resistance, and in the hub it is important to have fine-grained structure that provides higher strength.
It is characterized by a combination elongated in the radial direction coarse grains separated by thin layers of fine grains; this structure is typical for thermal deformation.
The experiments on generating disc regulated structure and its properties are described sufficiently detailed in a number of papers [1, 11].

There are about 20 grains along x,y axises,500 grains in total, and the initial grain size is about 50 um.
There are about 10 grains along x, y axes respectively and totally 100 grains in the model.
Each grain was subdivided by the grid set as shown in Fig.3 (a).
The number of nodes doubles during the process of dragging, but it remains unchanged while the prism being subdivided into tetrahedrons, as shown in Fig.3 (b).
Step 3, Drew the external boundary form 3D volume meshing of each grain to form the grain boundaries, then subdivided them with Quadrilateral.

It can be seen that the bSn grain structure in Sn-0.7Cu-0.05Ni contains multiple bSn grain orientations (colours in the Euler angle map of Figure 3(b)).
It can be seen that the bSn grains grow in a columnar mode from the Cu6Sn5 reaction layer and there are more bSn grains near the layer and a decreasing number of grains further away from the layer, which is indicative of grain selection by competitive growth from the nucleation site.
(c) bSn pole figures where colours give the orientation of the grains in (b).
Note that the grain structure is quite different in the Sn-0.7Cu-0.05Ni / Cu joint in Figure 4 and Sn-3Ag-0.5Cu / Cu joint in Figure 6 where multiple columnar grains grew in Figure 4 and two mutually-twinned grains grew in Figure 6.
A synchrotron imaging technique has been used to detect the nucleation and growth of primary Cu6Sn5 and EBSD has been applied to understand the differences in number of tin nucleation events and grain structures between the two solders.

The modification of liquid metal by electric pulse (EP) is a novel method for grain refinement.
These tests experimentally testified Wang's electric pulse modification (EPM) model that was built only by phenomenology and hereby the mechanism of grain refinement resulting from EPM is further elucidated.
So the present work focuses on the structure changes of the liquid aluminum remelted from EP-modified casting in order to experimentally examine Wang's EPM model and hereby illuminate the mechanism of grain refinement resulting from EPM.
Structural Parameters EP-Modified Unmodified Atomic density 0.0529 0.0531 Correlation radius (rc)[nm] 0.925 0.780 Average atom number per cluster (�at) 174 119 Coordinating number (�s) 9.063 8.546 The nearest neighbor distance (r1)[nm] 0.285 0.285 It is especially significant for the investigation of EP-modified liquid aluminum structure at 750°C, since at this temperature, the liquid aluminum was EP-modified and the optimal grain refining effect was obtained.
Large numbers of stable nucleus lead to inevitably the refinement of solidification structure.

The fatigue behavior of metals is strongly governed by the grain size variation.
In many microcrystalline (mc) and ultra-fine grain (ufc) metals and alloys, strengthening with grain refinement has traditionally been rationalized on the basis of the so-called Hall-Petch mechanism [2, 8].
Here the increased resistance to plastic flow is explained as depending on the pile-up of dislocations at grain boundaries and to the mechanism associated with the much more difficulty of the slip transfer between adjacent grains.
Even if a grain refinement leads to an increase in the number of cycles to failure at the same stress levels investigated, the results for very close microstructures results a strong function of the ductility.
The dislocation generation and locks formation is larger as decreasing grain size because of the grain boundary density, in this way the more the structure is fine the more such phenomenon is pronounced and the hardening increases as decreasing the grain size.

Machining Performance of Brazed Diamond Wire Saw with Optimum Grain Distribution B.
Because brazing can only improve the bonding strength and the high protrusion of grains, the three-dimensional distribution of grains at the tool surface has effective impact on the machining performance of tools.
So only by synthetically adopting brazing and optimum grain distribution, can the new generation monolayer tools ultimately make use of and bring into full play the intrinsic performance superiority and machining advantages of diamond grains.
Fig. 5 shows contrast feed speed versus accumulated cutting area for monolayer brazed diamond saw with optimum grain distribution and sintered one with random grain distribution under the condition of keeping the same load electric current and machining object.
Why the life and machining efficiency of monolayer brazed diamond wire saw with optimum grain distribution obviously outperform those of multi-layer sintered one with random grain distribution can be better understood if one observes diamond grits failing process during sawing shown in Fig. 6.

The neighbouring cells of type Liq from its nearest environment (N, S, W and E) are captured by the growing grain, thus creating type Int-2 with all the attributes of a grain of this type (i.e. number, orientation angle of crystal lattice, and phase type in the case of multiphase growth).
The neighbouring cells of type Liq present in the nearest vicinity are absorbed by the growing grain and acquire type Int-2 with all the attributes of a grain of this type.
The neighbouring cells of type Int-3, belonging to this grain, change their type into Int-2.
The attributes of none of the 8 closest cells will change, if the cells have already been captured by other grains.
In these equations the subscripts n and n+1 denote the iteration number, and the superscripts denote the indices of the neighbouring cells (see: Fig. 1).