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Two-step heat treatments were carried out to produce a systematic variation in microstructure with different interlamellar spacings but similar prior austenite grain sizes.
The microstructure is plenty of pearlite, and a small quantity of proeutectoid ferrite which proceeds along the prior-austenite grain boundaries as shown in Fig.1.
Interlamellar spacing, nm prior-austenization grain siz, μm Volume fraction of free ferrite, % 1# 140 60 3.1 2# 190 60 4.0 3# 280 60 7.3 4# 510 60 17.2 Results and Discussion The SEM macro-fractographs of tensile fracture surface are given in Fig.2.
In the neck regions of 1-3#, a number of “S”-shape bend and rotation were observed as showing in Fig.4.
Fig.5 SEM (a) and TEM (b) micrographs of the shear bands in neck region With the increase in interlamellar spacing, the number of “S”-shape bends and rotations noticeably decreases, and the cementite lamellae cut directly by the shear bands as showing in Fig.5.

Microstructure of heat affected zone indicated base metal adjacent to weld metal with fusion line and the affected area by the heating temperature of about 450-550 ℃ affect base metal was grown grain and weld metal revealed columnar grain into the weld metal.
Microstructure of weld metal indicated dendrite grain measuring approximately 20-30 μm.
Table 5 Results show the bending test Condition Accepted Number of specimens Al 6082 T6 4043 NW 5 Hz 4 4 Al 6082 T6 4043 R1 5 Hz 3 4 Al 6082 T6 5356 NW 5 Hz 4 4 Al 6082 T6 5356 R1 5 Hz 4 4 Fig. 5 Bending test specimens Conclusion From the analysis, the following conclusions have been drawn. 1.
Number of porosity increases after repair welding. 3.

The total number of counts in the measured spectrum is 5x10 6.
S-parameter is measured as the number of counts lying within an energy interval of 1.3 keV centered at the peak of the annihilation line.
The third annealing stage is observed from 623/ 650 to 823 K and attributed to complete recrystallization and grain growth.
The significant decrease in I2 and κ in the second stage is combined with a decrease in τav could be assigned to the formation of a small size vacancy clusters where I2 and κ give an indication of the number of defects in alloys.
On the other hand, the constancy of I2 for these samples can be explained due to minor changes in the relative number of positrons annihilating in the clusters during recrystallization.

An appreciable amount of intermetallic particles is still retained along grain boundaries after solution treatments for up to 60 hrs.
The number 6 means the total number of stacking layers contained in a unit cell is six.
Experimental Results Figure 1(a) provides a bright-field transmission electron micrograph and three selected area electron diffraction (SAED) patterns of the alloy in the as-cast state, from which one can see the irregularly-shaped intermetallic particles along the grain boundaries.

It can be distinctly found in Fig. 1c and Fig. 2c that precipitation of α phase in β phase matrix microstructure with large equiaxed grains and a large number of twin were generated after cold rolling in both titanium alloys.
The grains size of Ti-3873 titanium alloy are smaller than Ti-3573 by comparison.
Twin β grain Twin β grain α phase Twin Fig. 1 Microstructure of Ti-3573 titanium alloy after cold rolling and aging at 650 °C for (a) 3 h, (b) 6 h, (c) 9 h, (d) 12 h β grain Twin Twin Twin α phase β grain Twin Fig. 2 Microstructure of Ti-3873 titanium alloy after cold rolling and aging at 650 °C for (a) 3 h, (b) 6 h, (c) 9 h, (d) 12 h 3.2 SEM micrographs of two titanium alloys The SEM micrographs of two alloys after cold rolling and aging for 9h presented in plotted in Fig. 3 and Fig. 4.
Grains and twin are clearly visible in both titanium alloys as shown in Fig. 3b and Fig. 4b.
The Effect of Heating Rate on Discontinuous Grain Boundary Alpha Formation in a Metastable Beta Titanium Alloy[J].

The results show that, with the increase of the substrate temperature, XRD peaks become sharper, the grain sizes grow up rapidly, and the crystal structure is improved gradually; the surface topography become like the islands and the haze achieves 16.47%.
SnO2 films are n-type semiconductor for its imperfect crystal lattice and nonstoichiometry as a result of the presence of a large number of oxygen vacancies, provide electron of 1015~1018cm-3 to conduction band [3, 4].
From Fig.2 it can be seen that the grains on the surface are incompact and have many pores, which exhibited a uniformly granular structure at low substrate temperature.
It. reveals that the films crystalline imperfectly under 400, with the increase of the substrate temperature, the average crystalline grain size grow up and the diffraction peaks become sharper and more strength.
With the increase of substrate temperature, carrier mobility increase as the grain boundary decrease, the rate of the free electron diffusion may become higher, and then the conclusion arrived at the lower sheet resistance.

The main phase of the alloy is Ferrosilide FeSin, along the grain boundaries of which a carbide phase is precipitated represented by small particles of Cr2C3, Cr7C3 carbides of regular and acicular shapes, as well as large particles of special chromium carbides (Cr,Fe)7C3, (Cr,Fe)23C6.
By now, a number of new surfacing materials possessing a complex of new physical and mechanical properties and complying the current requirements of both processing of agricultural products and induction surfacing have been obtained.
The main phase is Ferrosilide (gray areas), which crystallizes into coarse-grained acicular and lamellar structures, along the grain boundaries of which a carbide phase is precipitated in the form of small particles of Cr2C3, Cr7C3 carbides of regular and acicular shape, as well as large particles of special chromium carbides (Cr,Fe)7C3, (Cr,Fe)23C6, which turn purple when etched with Murakami’s reagent.
Small inclusions of brown colored FeB and Fe2B borides are observed in the grains.
In addition, very small drop-like red precipitates of copper are visible over the entire area of the material with insignificant segregation along the grain boundaries.

These polymer microspheres were characterized by Scanning Electron Microscope and Grain Size Analyzer.
Numbers of 25 mL of Pb(NO3)2 solution were placed into numerous conical flasks with plug, and 0.1 g of starch based polymer microsphere was added into these solutions, respectively.
It could be seen that average grain diameter of starch based polymer was 43.9 μm and had a narrow distribution size.

Grain refining is an effective method to increase the yield strength and tensile strength without impairing good ductility.
Austenitic stainless steels do not exhibit any transformation during hot deformation, so grain refinement can be achieved only by recrystallization.
The best number of units in the hidden was determined by trying and erroneous (examined from 1 to 12).
∑ ∑== − = N i P j jiji RMS yd PN E 1 1 2 )( 11 （3） where EPMS is the average root-mean-square, N is the number of training or testing data, p is the number of variables in the output, dj and yj is the target output and network output for neuron j respectively.
Fig. 2 shows the root mean square error for both testing data and training data for various numbers of units in the hidden layer by means of trainbr algorithm.

The number of cracks and their width increased with the increasing bending angle.
(1) The total cells number is given by equation (2)
(8) Then the number of cells on the surface and the ratio of the surface cell number over the total cell number is, (9) (10) The total cell number and the proportion of the surface cells to the total crystal cells of the whole particle are showed in figure 5 below.
Fig. 5 Number and proportion of the surface cells versus the size of nanoparticles.
However the metal-base material (SS substrate) plays the main role, whereas the grains of the reinforcing materials (MgB2 thin films) are less significant.