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Ti inoculation level was changed up to 0.1wt% by adding Al-10Ti master alloy into 3003 aluminum melt as grain refiner.
A number of components are press-formed at room temperature and then assembled to a net shape.
An Al-10Ti master alloy was used for grain refining of 3003 alloy, and the consequent effect of grain refinement on strength and formability of the clad aluminum sheet was examined through tensile tension test and hemispherical dome stretch test.
Grain refinement significantly increased the biaxial formability of the 4343/3003/4343 clad sheets by 2 times or more.
It appears that an isotropic and fine grain structure was more favorable to biaxial formability.

The grain size of the 1% Mn steel is coarse.
By contrast, the grain size of 2% Mn is quite small.
Also the number of the transformation nuclei is changed.
Rex. 3) Number of transformation nuclei The progress of the transformation is slightly faster with increasing the number, and the transformed grain size decreases (Fig.4(c), Fig.6).
In the experiments, when the transformation initiates at an early stage of the recrystallization, the number of the transformed nuclei increases; this can result in a refined microstructure because the nucleation of the transformation can occur not only at the grain boundaries but also within the deformed grains, which have larger dislocation densities.

The results indicated that there existed large amount of nano/micro-scale grains produced by sputtering and impacting of the melting Al-Si jet.
Meanwhile, some sub-micron grains at the interface were observed, and selected area electron diffraction (SAED) pattern represented typical Face-Centered Cubic (FCC) features of Aluminium alloy.
The grains in nano phase area were basically isometric crystalline, its size were smaller than 100nm.
The existence of metal stable nano-scale grains in Al-Si coating would evidently improve the interface activity and promote formation of metallurgical bonding.
Analysis of deposition behavior of Al-Si particle coated on ZM5 magnesium alloy elucidated that there existed a majority of ellipsoidal sub-micron scale grains at the edge of flattening particles.

On all EBSD maps shown in the following figures Cube grains are marked blue, S grains – green, Cu grains – red and Brass grains – yellow.
To compare the nucleus density from different nucleation sites, the number of nuclei developed from large Cube bands was also counted.
The results revealed 42 recrystallized Cube grains from 24 large Cube bands on the same sample area, i.e. on average 2 Cube grains per large Cube band.
In general, it is well known that the Cube orientation has a highly mobile high angle grain boundary with S-grains due to a special 40°<111> orientation relationship.
Hence, Cube nuclei with highly mobile grain boundaries to S-grains were preferred and showed the highest growth rate compared to nuclei having grains of other orientation as next neighbors.

The average αp grain size is about 25 µm and the former β grains have a mean diameter of 60 µm.
The rotation angle ω around a given axis R defines the rotation which allows to pass from the reference frame of an αp grain to that of an αs grain.
The illustrative example presented in fig. 6a shows an isolated β grain and the adjacent αp grains (numbered from 1 to 7).
The αp neighbour which has the c-axis, the closest to a <110>β direction is number 5.
Similar results were observed for other isolated β grains.

The change of number, morphology and distribution of precipitation phase are the important facts to make the alloy strengthen.
It’s shown that tiny equiaxed dynamic recrystallization grains appear gradually along grain boundary after hot compression.
Compared to T5, the size of these large grains is little difference.
A large number of precipitated second-phase particles are produced after T6 heat treatment, as shown in Figure 2(b).
It shows that the number of the dimple is little and fracture morphology is mainly stonelike after T6 heat treatment, as shown in Figure 3(b).

After conventional melt-treatment, there were still a number of oxide inclusions, still distributed non-uniformly and gathered together; but their size decreased to about 10-20μm.
After high-efficient melt-treatment the number of inclusions was decreased obviously, and distributed along grain boundary or within the grain very uniformly (about or less than 4μm), and no congregation of inclusions was found in this material.
From Fig.1 it can be seen that the high-efficient melt-treatment can decrease effectively the number of inclusions and improve their existing morphologies.
The inclusions congregated in a large lump form and distributed non-uniformly along grain boundary.
After high-efficient melt-treatment, the number and content of inclusions in molten Al have decreased remarkably, and their size was very small [2-4].

Electropolished specimens were also examined by scanning electron microscopy using atomic number and channelling contrast in the back-scattered electron mode.
Grains in the core alloy are distinguishable by virtue of channelling contrast while the Mn-rich dispersoids appear much brighter because of their higher average atomic number and the solidified eutectic shows as a fine network of silicon flakes.
Grain growth has taken place where grain boundaries were replaced by liquid films.
Examination of a number of different areas indicated that the threshold condition for wetting corresponds to a misorientation of about 7 o.
Regions marked A show where the melt has wetted grain boundaries in the alloy and migration of these liquid films has led to grain growth in the outer layers of grains.

The FΣ3 parameter has been defined as the relative number of high angle boundary segments, in the range from 15º to 65º misorientation, satisfying a Σ3 relationship within a fixed tolerance.
In-grain level: Different OIM options have been used here to define parameters that can be related to the in-grain microstructure.
θθθθm [º] F[1º,15º] K [º] OSA [º] Related distance ∆d ∆d 2∆d Over the grain Table 2.
Conclusions The effect of monotonic and strain reversal conditions on the microstructure has been studied at two levels (grain boundary and in-grain).
Proceedings of First International Conference Recrystallisation and Grain Growth, Eds.

The plastic flow in fine-grained, polycrystalline Al2O3 takes place mainly by grain boundary sliding or grain boundary diffusion.
The segregated dopant cations change the grain boundary diffusivity and/or the grain boundary sliding itself.
Figure 6 (a) shows a HRTEM image of a grain boundary in Y 3+-doped Al2O3, together with EDS spectra taken from grain interior (b) and the grain boundary (c) using the probe size of 1nm [12].
Moreover, the presence of Y 3+ cation can be detected only from the grain boundary, but not from the grain interior.
These ideas attributed the effects to increment in the number of CSL (Coincidence Site Lattice) boundaries by the dopant [22] and to ionic sizes of the dopants [23].