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If parallel Widmanstätten austenite laths form in two adjacent ferrite grains, zig–zag ferrite grain boundaries arise.
Detailed analysis reveals that coarse ferrite grains are fragmented into a number of subgrains with misorientation less than 2°.
Fig. 3a shows a straight ferrite grain boundary.
Precipitates occur along grain/subgrain ferrite boundaries and also inside ferrite grains.
In the case of the nucleation of Widmanstätten austenite laths on both sides of the ferrite grain boundary, zig–zag ferrite grain boundaries arise because flat facets at ferrite grain boundaries are not parallel due to misorientation between the grains. 3.

Discussion The number of microcracks nucleated by each microstructure for the tested temperatures for the rolling direction is shown in Table 2, which also shows that the number of microcracks decreases with test temperature.
Therefore, a smaller number of microcracks will be developed in a smaller volume of the strained material.
Number of microcracks for each fracture initiation microstructure in the rolling direction.
At –60ºC the number of microcracks decreased about 60%.
Number of microcracks for each fracture initiation microstructure in the transverse direction.

The number of grain boundaries along the propagation direction of cracks and the amount of substructures after heat treatment increase with the decline of thicknesses of 2124 alloy plates, while the grain size is reverse.
Different plate thickness is due to different deformation during the hot padding, so grain size and number of grain boundaries appear obvious different in different plates, and maybe it is because of the difference of the microstructure determines the propagation rate of fatigue crack, which ultimately affect the fatigue life of the alloy.
Besides, coarse Al6 (Mn) phases are also observed inside the grain and on the grain boundaries [9].
It is reasonable that the number of boundaries along the propagation direction of cracks increases with the decline of thicknesses of alloy plates.
The smaller plates thickness are, the smaller grains size is, the more number of grain boundary and substructure and the higher the fatigue life of alloy is, that is to say, the better fatigue performance of the alloy is.

Table 1 :ITOSample description Sample Number Of Layers Deposition Time(min) 1 1 5 2 2 10 3 3 15 4 4 20 5 1 30 6 2 60 7 3 90 8 4 120 Start Sample Preparation Indium Tin Oxide(ITO) Deposition Annealing Process(Treatment) Characterization & Analysis Aluminium (Al) Deposition Atomic Force Microscopy(AFM) Figure 1 : Process Flow Results and Discussions The AFM images are analyzed to gain information on the surface roughness and the grain size of the samples.
The grain size recorded shows highest result from sample 4 with 27x104nm2and the lowest is from sample and which records grain size value of 3.65x104nm2.
It shows that deposition time used during the process does play part in determining the grain size of the sample.
Sample 2 Sample 1 Rrms= 5.72nm Grain Size=8.15x104nm2 Rrms= 12.7nm Grain Size=15.5x 104nm2 Sample 4 Sample 3 Rrms= 24.6nm Grain Size=27x104nm2 Rrms= 18.7nm Grain Size=17.2x104nm2 Rrms= 8.34nm Grain Size=8.08x104nm2 Rrms= 43.6nm Grain Size=24.8x104nm2 Sample 6 Sample 5 Sample 8 Sample 7 Rrms= 6.41nm Grain Size=4.16x104nm2 Rrms= 10.8nm Grain Size=3.65x104nm2 Figure 2 : AFM images, surface roughness value and grain size value Conclusion As an overall conclusion of this study, the deposition time of the ITO layer does play an important parameter role in future study using the ITO material.
Deposition time do change the grain size of the material which will be an important aspect when using this material in fabrication of any device mainly in opto-electronic field where grain size do play a major role in the electrical and optical charateristics.

In the pure Cu, the nano-sized grains were formed after third cycle with an average grain size of 200nm.
Once the 200 nm grains formed, further reduction in the grain size was not observed up to the 8 ARB process cycles.
This behavior is also reported in some Al and Ti alloys [6]. 0246810 0 100 200 300 400 500 Tensile Strength (MPa) Number of cycles OFC PMC-90 02468 0 10 20 30 40 50 Elongation (%) Number of cycles OFC PMC-90 Fig. 1.
A large number of dislocations began to be observed in both alloys after the first ARB cycle.
The increase in strength with increasing number of ARB cycle is attributed to the strain hardening in the initial stage.

Results show that ultrafine grains + nano-carbides are obtained in the steel plates.
Introduction Recently, ultrafine-grained materials with mean grain size of less than 1μm have been energetically studied, because they are expected to bear superior mechanical properties to conventionally coarse grained materials.
The SAD patterns were arc-like, which suggests that a number of the high-angle boundaries (>15°) exist within the selected areas of Fig. 1b [6].
Annealing above 873 K, the microhardness decreased slightly but the grain size grew rapidly.
Annealed at 873 K, the equiaxed ferrite grains + nano-carbides formed in most of the areas as shown in Fig. 3c.

Kinetic strength in grain growth is evaluated for HAZ of welded pipes.
The grain growth is assumed diffusion controlled and Arrhenius temperature dependency is applied for the rate of growth in grains.
Thermal cycle induces the number of diffusive jumps and exploring the grains, and in a non isotherm cycle the intensity of the diffusive jumps can be evaluated by the term of kinetic strength as it is suggested by Ion et al. [1].
The grain growth is obtained from the computation of equation 3, where go is the grain size in parent metal.
Mohanty: A modified analytical approach for modeling grain growth in the coarse grain HAZ of HSLA steels, Scripta Materialia, Vol. 50 (2004), p. 1007-1010

The transverse (sub)grain size and the number fraction of high-angle (sub)grain boundaries within the austenite phase were about 0.4 µm and 17%, respectively.
All the clearly defined (sub)grain boundaries were taken into account to determine the (sub)grain sizes and the (sub)boundary misorientations.
The transverse sizes of phases and (sub)grains decrease with increasing the strain.
The numbers indicate the (sub)boundary misorientations in degrees.
Misorientation, θ (deg) 0 10 20 30 40 50 60 0.0 0.1 0.2 0.3 0 10 20 30 40 50 60 ε = 4.4 ε = 2.0 ε = 0 0.0 0.1 0.2 0.3 Number Fraction, Ni / N 0.0 0.5 1.0 ε = 0 ε = 2.0 ε = 4.4 Austenite Ferrite Fig. 4.

Introduction Grain boundary engineering (GBE) evolved from "grain boundary design and control" [1-4] has proven to be an effective method for improving various properties of bulk materials.
Numerous studies have shown that these special grain boundaries, described in low  coincidence site lattice (CSL) grain boundaries (usually 29) possess special chemical, mechanical, electronic, kinetic, and energetic properties [5-11].
At the critical strain, some of the grain boundaries are distorted by extrinsic dislocation, which will induce the rapid growth of some grains when the materials are annealed at a high temperature.
Grain boundaries with 129 were regarded as special CSL boundaries, and Brandon's criterion was applied to determine the  number for all boundaries.
On the other hand, abnormal grain growth occurred under the effect of heat input.

We prepared three groups of specimens which were quenched a different number of times.
The length of grains was calculated by using the following equation: l=LnL (Eq. 1) where the L is the length of the line (mm), l is the average size of the grains (mm), nL is the total number of the number of interceptions and 0.5 which is a modification number for broken grains on the periphery.
The average carbide particle size increased with the number of quenchings.
The roundness values in each group of the number of quenching times were similar.
Acknowledgment This research work was supported by JSPS KAKENHI grant numbers 19K14875.