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There were both equiaxed and elongated grain, which average grain size of was 18μm.
The second phase not only pinned on the grain boundary, but also in the grain.
The grain was elongated obviously.
The elements which has High z number must exist in this phase due to it was brighter and bigger than other two phases shown in Fig.4 (e).
Both of the two elements were rich in the grain boundary to restrict the growth of grains.

As semi-solid alloy crystallizing, the certain solidification conditions are controlled, such as pouring temperature, cooling rate and grain refinement, to maximise grain nucleation and suppress dendritic growth, thereby preparing the microstructure with fine-grained and nondendritic.
The aluminium alloys are grain-refined by addition of a grain refiner (Ti-based refiner) prior to casting to ensure heterogeneous nucleation.
There is no significant change in grain size, as shown in Fig.1b.
The micro- structure at the edge area consists of thin and long dendritic-like grain and a certain amount of dendritic-like grains not fully changing into rosette-like primary phase, as shown in Fig.3c.
The microstructure prepared without the stirring and the refiner basically consists of a little rosette-like primary phase and a great number of dendritic-like grains not changing into rosette-like primary phase in the transition and edge area, in which the requirement on rheocasting is not satisfied.

Small-angle grain boundaries decrease or even disappear.
The Al3Ti grain size is approximately 500nm.
The lower-angle grain boundaries (<15 º) are about 3.12% , which showed characteristics of the high-angle grain boundaries.
This is because that a larger number of materials deforms during REA process.
The risen deformation temperature, the alloying formation and recrystallization occurred resulted in an increasing number of high-angle grain boundaries.

It can be seen that the grains are un-uniform where the bigger grains are surrounded by many small grains.
The microstructure is shown as Fig.1 (b) which has uniform grains with an average grain size of ~16.4μm.
The grain size was determined using a linear intercept method from a large number of non-overlapping measurements.
At room temperature, due to strengthening of grains, and grain boundaries by lots of fine precipitates and solute atoms, dislocations were difficult to glide in the interior of grains and grain boundaries were also difficult to move.
Summary Grains are refined significantly by ECAP.

Introduction The current interest for the production of fine grained materials by severe plastic deformation (SPD), leads to a large number of investigations focusing on the substructure development and the related mechanical properties.
Both materials were received in as cast condition with an initial grain size of ∼250 µm.
For alloy AA5182Cu these numbers are after 4 ECAP passes 24% HAB and an average (sub)grain size of 2.3µm, and after 8 ECAP passes 42% HAB and 1.4µm (sub)grain size.
� Grain refinement in alloy AA5182+Cu during ECAP, is delayed compared to alloy AA5182
The authors are also grateful for the financial support provided by the Belgian Science Foundation (FWO) under contract number G.0208.02.

Analysis of Kinematics of Single Diamond grain There are several kinds of conditioning trajectories of a diamond grain bonded on the stainless steel substrate for different relative motion modes between polishing pad and conditioner and array types of diamond grains.
Secondly, the number of trajectories in every sub-district is calculated base on the principle of pixels statistics.
(3) Where, sk is non-uniformity coefficient and is taken to be 0.1, stdN is the standard deviation of trajectories number in whole sub-districts and avgN is the average of trajectories number in whole sub-districts.
The only difference is that the period of n1 is longer than the period of n2 in the same conditioning time, leading to fewer period numbers of n1.
So at the same speed ratio, rotation speeds affect nothing but period numbers.

Pancaking of the austenite grains means more preferential nucleation sites for ferrite and accordingly to finer ferrite grain sizes.
Grain and subgrain growth are controlled by the movement of grain/subgrain boundaries.
The new dislocation free grains grow and consume the old grains, leaving a new structure with low dislocation density as a result.
The fraction recrystallized in the material is the number of recrystallized grains, Nrec, times the mean volume of the recrystallized grain.
The final predicted austenite grain radius is about 12 µm.

In fact, grain boundary motion towards grains with a higher diamagnetic susceptibility under impact of strong magnetic fields in crystals with a hexagonal lattice was reported [6].
Since the materials are characterized by a large grain size, the number of analysed grains in a single measurement was comparable small, leading to an estimation of the grain size without a statistically reliable characterization.
The grains are colour-coded according to the inverse pole figure map shown as inset.
As a matter of fact, we found that the annealing in magnetic field changes the morphology inducing double-seam structures at a larger number of GBs.
[5] Molodov DA, Gunster, C, Gottstein G, Grain boundary motion and grain growth in zinc in a high magnetic field, J Mater Sci 49 (2014) 3875-3884

These grains develop specific features that can be attributed to grain competition and concomitant poisoning of growth caused by the rejection of aluminum in the melt.
Yet, their thermal behavior (high Prandtl number) is significantly different from metallic systems (low Prandtl number).
In all cases, the grains display facets all along growth.
The interface between the liquid and the two grains shows a cusp at the level of the grain boundary, and there are merely two facets on the left grain and three on right grain.
Nucleation and growth of new quasicrystal grains.

When examining welded joints, the microhardness method is used, which makes it possible to obtain a large number of indentations in individual zones of welded joints, obtaining statistically reliable data.
At the same time, the lower microhardness of cast steel 245-260 correlates with a coarser grain size (≥ 500 μm) and a lower yield strength of cast austenite nitrogen.
The nitrogen concentration in the fusion zone is high, and the grain size is minimal in comparison with all other zones of welded joints of rolled products.
In the heat-affected zone of the weld metal at welded joints of cast steel, the microhardness also correlates with the grain size, i.e. does not change.
Unlike welded joints of rolled products, welded joints of cast steel have a grain size in the fusion zone that is not the minimum of all zones; the smallest grain size is in the weld metal.