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EBSD analysis allows for the determination of microstructural parameters at a refined scale including grain size, grain misorientation, crystallographic and morphologic texture, and phase ratios, which can be employed to establish a correlation between microstructural changes and deformation mechanisms with temperature.
Mappings were post-processed via the spherical indexing process, which yields high-quality indexation (with a reduced number of points exhibiting a Confidence Index of less than 0.1), even at high strain levels.
However, it remains difficult to clearly predict the hierarchy of the different deformation mechanisms, which is strongly dependent of the microstructure (texture, grain size, phases…) and the temperature.
The processing workflow included re-indexing (combining spherical and neighbour pattern averaging indexing), followed by two clean-up steps (grain dilation and Confidence Index (CI) standardization).
This approach enabled high-quality EBSD maps, significantly reducing the number of points with CI values below 0.1, even at high strain levels [9].

However, some microstructures also provide a number of irreversible hydrogen traps, such as grain boundaries or incoherent interfaces between particles/inclusions and matrix.
The normalised transfer bar exhibits a ferrite-pearlite microstructure with grain sizes in the range 10-15 µm.
These differences are associated with the different numbers of hydrogen traps present in the microstructure of the respective samples [4].
This is a consequence of its larger grain size.
A coarse grained microstrucure is less efficient in trapping hydrogen.

Unfortunately, due to their hexagonal close-packed (HCP) structure, the limited number of independent slip systems at room temperature can not satisfy the Taylor criterion for generalized strain [4].
When tested at 150℃, the straight grain boundary implied no DRX.
Twinning was observed within some originated grains at this temperature.
A big volume fraction of small new grains were formed in the “necklace” shape, and the remained certain number of originated grains implied that DRX was incomplete.
The volume fraction of new grains was sharply decreased with increasing strain rate.

The results show the grain diameter of quartz sand powder is gradually decreased, the grain fineness distribution is tapered narrowing.
Results and discussion Fig.1 Effect of the ball milling rotate speed on the grain diameter of quartz sand powders.
The relation of ball milling rotate speed and particle size of quartz powders is shown in Fig.1, which shows the mean grain size of quartz powders are decreased vary with an increasing the ball milling rotate speed.
Because the rotate speed is increased, the milling number and the acting force between ball milling media and quartz are both increased, it makes the effect of ball milling strengthen, the particle size of quarta powders are decreased.
Conclusions The mean grain size of quartz powders are decreased vary with an increasing the ball milling rotate speed.

The surface of the target was abraded by sand paper number 1200 and then cleaned with acetone in an ultrasonic cleaner for 5 minutes.
The exposure time (Ton) varied from 10 to 30 seconds, related to the amout of the pulse number for each Ton.
Results and Discussion Fig.2 (2a) to Fig.2 (2c) illustrated the small grain size and the average thicknesses were about 90.2, 340.5 and 460.5 nm, respectively.
The condition A4 illustrated the bigger grain size due to the thermal effect of the target to thin film was higher than others conditions while the average thickness was about 736.7 nm and illustrated in Fig. 2 (2d).
The thickness and the grain size of thin films at 10 seconds of exposure time, using the chopper was smaller than without the chopper while the thickness increased as the exposure time increased at a constant speed of the chopper.

Obviously, grain size and dislocation motion resistance are influencing factors of the deposited layer hardness, so all conditions of refining grain can increase the hardness.
The more nuclei becomes, the more growing point of grain becomes relevantly.
In this way, the grain size is reduced and the organization is defined.
This makes the density of grain boundary increases but limits the glide of dislocation, so does the hardness of coating.
Conclusions (1)Jet-electrodeposition effectively reduced the size of the grain, so that it increases the density of the grain boundary and limits the glide of dislocation.

Higher deformation at the final stage of rolling favors grain refinement.
To the austenite grain growth formula was used: t T Addcr ⋅      =− 3 30 exp3 3 β α α (10) where: t - time since the beginning of growth, crd - size of the grain after growth, 0d - size of the grain before growth.
a) b) 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 1-r 1-2-c 2-r 2-3-c 3-r 3-4-c 4-r 4-5-c 5-r 5-6-c 6-r 6-7-c 7-r 7-8-c 8-r 8-9-c 9-r 9-10-c 10-r 10-11-c 11-r 11-12-c 12-r 12-13-c 13-r Number of stand (rolling, cooling) Grain size [µµµµm] minimum average maximum 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 1501-r 1-2-c 2-r 2-3-c 3-r 3-4-c 4-r 4-5-c 5-r 5-6-c 6-r 6-7-c 7-r 7-8-c 8-r 8-11-c 8-11-ac 8-11-c 11-r 11-12-c 12-r 12-15-c 12-15-ac 12-15-c 15-r 15-16-c 16-r 16-17-c 17-r Number of stand (rolling, cooling) Grain size [µµµµm] minimum average maximum r - rolling, c - cooling, ac - accelerated cooling Fig. 3.
As a consequence, the grain grew.
After pass no. 12 in Version II, an average grain size of 13 µm was obtained.

Fig. 1 (a) shows unreinforced LM26 alloy is composed of grain boundaries, pores and intermetallic compounds at the grain boundaries.
The microstructure is composed of small size grains and Chromium Oxide particles located at the grain boundaries.
When the weight percentage of Chromium Oxide particles increases, the number of heterogeneous nucleation sites also increases which in turn increase the number of fine size equi-axed grains.
In addition to this the grain growth is hindered by the presence of Chromium Oxide particles thereby contributing to the grain refinement.
The increase in strength was attributed grain refinement and hardening.

The grain size was measured by mean grain diameter method.
This microstructure has an average grain size 44.38 µm, minimum grain size 16.7 µm while maximum grain size was 139.53 µm.
ASTM grain number was also calculated by using following formula [12].
n = 2(N-1) (1) Where n = Average number of grains per square inch at 100X magnification.
N = The ASTM grain size number.

At 60 s, uniformly distributed dimples can still be seen on the Cu side, while the Ti side shows tearing edges and a small number of dimples.
At 50 s, the undulation of the interface is milder than before, but a small number of discrete micro-pores appear locally.
Under the condition of 30s pulse current heating, at low temperature, the grains on the Cu side exhibit an obvious elongated morphology along the rolling direction (RD) with dense grain boundaries; the grains on the Ti side show broken and refined characteristics, exhibiting a significant work hardening effect.
Under the 40s pulse current heating condition, the grains on the Cu side undergo partial dynamic recrystallization leading to partial refinement, but the overall grain size increases slightly.
On the Ti side, the grains begin to recover and grow due to temperature and diffusion, dislocations decrease through rearrangement, the grain size increases slightly, and dislocation slip is enhanced.