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As shown in (a), when the concentration of the reactant is 0.01 mol/L, the surface morphology of the film appears uniform and regular, the number of pores increases, the arrangement is dense, and the direction is oriented toward the ordering.
Due to the high salt concentration, the crystal grains are deposited.
Together, the porosity is not large enough, the grain growth is irregular, and there are obvious signs of grain growth.
The reason for this is that the salt concentration is high, the crystallization driving force is large, the nucleation rate of the crystal grains is large, and the crystal grains are large, and an oxide film having a thick and no obvious undulation is easily formed on the surface of the FTO glass.
As a result, the adsorption capacity of the crystal on the dye is large, and the number of dye molecules adsorbed is more, which has a positive effect on increasing the photoelectric conversion rate.

The obtained galvanic replica of the mould insert, which is later applied in the injection moulding process, can only be used for a limited number of cycles due to insufficient quality caused by surface wear [2].
The compact character of the short piled pad prevents the diamond grains from penetrating deep into the pad, causing the grains to stick out and removing material by grooving.
The longer fibres and less compact character of the pad allow the grains to penetrate deeper into the pad, causing them to stick out lesser and even permit free movement of the grains (three-body-abrasion).
Regarding the grain size dg of the diamond suspension, a linear trend can be detected, which implies that an increase in the grain size leads to a rougher surface.
Obviously, the choice of the polishing pad predominates the other two parameters polishing time and grain size.

Thus the number of alloy grades used for plastic working is significantly smaller in comparison to casting alloys.
The primary steps, as can be seen in Fig. 7 c-d, occurred on the α-Mg grain boundaries.
Their systems are generated in various planes, in the area of individual α-Mg phase grains, demonstrating various crystallographic orientations.
Thus the secondary steps „S” (Fig. 7 c-f) occurred on the boundaries of individual grains in the process of fatigue crack propagation.
Kainer, Hydrostatic extrusion of commercial magnesium alloys and its influence on grain refinement and material properties, Material Science and Engineering A 424 (2006) 223-229

Yttrium aluminum garnet (YAG) materials have a number of unique properties and their application is extensive.
The microstructure in Fig.4-a shows as a large number of ceramic particles fused together in liquid phase.
The formation of a large number of sintered necks should be developed to determine its mechanical properties.
In the sintering process includes three stages, grain growth stage, grain boundary expansion stage, pore change stage, the main factors affecting the sintering temperature and holding time, sometimes the sintering atmosphere will also affect the microstructure of the ceramic in the process.
Jiang, Unique mechanical properties of nano-grained YAG transparent ceramics compared with coarse-grained partners, Mater.

And uniform grain was distribution on the film surface.
For the perovskite structure (ABO3) material, the impurity ions may be substituted A sites or B sites and the lattice may not occupy any position then into the grain boundaries when the impurity ions doped the material structure, thereby changing the properties of the material and the shape appearance.
It can be seen from Fig. 1, the grain of the LSF film which substituted by the elements significantly larger, the surface of film is smooth, without cracks, crystal grains are uniform distribution, without no large voids and other defects.
Because of different ionic radii, when substituted into the lattice element, the lattice constant is changed (larger or smaller), the grain size change, the number of changes in the grain boundaries, εr of the film increased or decreased.
From the SEM of film with the optimum dielectric properties, surface morphology of the films dense, grain size is uniform.

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The inset in (a) is a magnified part of the grain boundary.

There is an obvious transition layer called white band near the interface, as shown in Fig. 1a, the microstructure of columnar grains is perpendicular to the interface, and then the columnar grains transform to cellular dendrite, as shown in Fig. 1b, and then to flocculent microstructure near the surface due to the changes of temperature gradient from the molten pool to surface of the layer during the laser irradiation.
According to the model of heat input in laser cladding process proposed by Hoadly [14] as shown in Fig. 2, the solidification rate (Vs) can be given as follows: Vs=Vbcosθ (1) Where Vb is the scanning speed of laser beam, θ is the angle between Vs and Vb. the θ is about 90° near the bottom of molten pool, while the θ is the smallest near the surface of molten pool, so the rate of temperature gradient to growth rate (G/R) decreases from the bottom of molten pool to the surface and planar growth becomes unstable due to constitutional undercooling, the microstructure turns into columnar grains.
And the number of (Cr,Mo)23C6 phases is relatively high, while the number of Cr7C3 phases is low compared to (Cr,Mo)23C6 phases.
The microhardness of the clad layer reaches 720Hv, which is about 3 times larger than that of the 316 stainless steel substrate, the high microhardness of the clad layer results from the effect of solid solution strengthening and grain boundary strengthening.
And the number of (Cr,Mo)23C6 phases is relatively high, while the number of Cr7C3 pahses is small

The number of stacking faults in polycrystalline SiC was abundant, and the interfaces between crystals were apparent.
As crystals gradually grew and thickened, the edges of growing crystalline grains of different orientations came into contact with each other as shown in Fig. 3.
A large number of pores could be observed at the grain boundary.
The grain size was smaller – about a few micrometers.
Moreover, there was a layer of amorphous film, about 100nm, on the surfaces of grains at the interface.

Among these mechanisms there are crystallographic slip in grains of β-Zr and α-Zr as well as mutual displacements of crystallites along interphase boundaries.
Treatment of measured data, that is construction of texture pole figures (PF) and determination of their parameters, was carried out by the software, including a number of specially elaborated programs.
Deformation development can be either crystallographically regulated, as in the cases of intragranular slip in α−Zr and β-Zr, having HCP and BCC crystalline lattices, respectively [4], or realized by a non-crystallographic mechanism, as in the case of mutual displacement of grains by interphase boundaries within a fine-grained mixture of two phases under conditions of α↔β transformations [5].
Crystallographic slip results in arising of preferred grain orientations, or crystallographic textures, whereas activation of non-crystallographic mechanisms causes texture scattering.
If the temperature of preheating was not sufficiently high for growth of β-grains, so that β-Zr remained fine-grained, its compression results in formation of the texture, typical for deformed polycrystals: by the same main components, texture maxima are much wider (Fig. 2-b).

Tab1 Different process of heat treatment Numbers Disposing Technology 1# 2# 3# 4# 5# 945˚CSolution 30min AC+600˚C4h AC 955˚CSolution 30min AC +600˚C4h AC 965˚CSolution 30min AC +600˚C4h AC 975˚CSolution 30min AC +600˚C4h AC 985˚CSolution 30min AC +600˚C4h AC Result and discuss Organization character Figure1 (a) ~ (e) are optical micrographs of different bimodal microstructures which were obtained by different technologies of heat treatment.
In the bimodal microstructure, secondary α is formed along metastable-β grain boundaries, and α lamellar structure are present inside colonies of lath-type β, so the microstructure is composed of white primary α and secondary α/βturn after disposition at 945˚C~ 985˚C.
a b d e c Fig.1 The micrographs of bimodal microstructures by heat treatment process under 200 (a)1#945˚C (b)2#955˚C (c)3#965˚C (d)4#975˚C (e)5#985˚C Tab 2 The quantitative analysis of primary α of five bimodal microstructures Numbers Proportion of Primary α(%) 1# 2# 3# 4# 5# 49.57 35.33 24.67 16.24 8.95 Quasi-static compression tests Fig.2 presents true stress-strain curves and the relationships between fracture strength, fracture strain and the content of primary α obtained from quasi-static compression test.
In respect of compression strength, on one hand, the content of secondary α increases because of the decrease of primary α, and the secondary α can improve the strength due to precipitation strengthening, furthermore, the decreasing of lamella thickness (metastable β grains) leads to fine-grain strengthening behavior on bimodal materials; On the other hand, the length of metastable β grains increases as shown in Fig.1, the α has hexagonal-close-packed structure while β has body-centered cubic structure, and the size of β grains decides the slip distance when the materials are under loading [4], thus the increase of β grains’ length results in the decrease of strength.
When the secondary α content is less, the failure mechanism is mainly about that the vacancy nucleation, growth and at last connect to each other and lead to the fracture; When the secondary α content is more, phase boundary increases due to the alternative distribution of secondary α and β grains so that the failure mechanism changes.