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In recent years, for grain refinement, severe plastic deformation methods has been used.
A similar technique appears to be ECAP-Conform as a continuous processing of ultra fine grained Al (Fig.5) [7].
Results and discussion Pressing pressure versus number of passes by route A, for fixed and movable die walls, is shown in Fig.7.
The ECAE pressure has increased slightly with increasing of number of passes due to strain hardening.
Hardness, 0.2 % yield stress and fracture elongation versus number of ECAE passes are presented in Fig.8.

Generally, the high temperature deformation of fine-grained materials is utilized for shaping.
Surprisingly, no significant differences such as grain elongation or grain growth were found between (a) and (b).
It is interesting that there are very limited numbers of crystallographic orientations for the D022-Al3Ti and A15-Mo3Al phases within the observed area originating from the former large A2-β parent grain.
As the shape of the grains were almost kept identical before and after the deformation, the change of the grain orientation distributions clearly shows the grain boundary sliding and grain rotating during the high temperature compression tests at which the strain-rate-sensitivity, m, ranges from 0.3 to 0.4 [2].
These results suggest the grain boundary sliding and grain rotating occur during the high temperature deformation.

Coarsening of deformed grains is not permited.
Results For the examination of grain coarsening every cell is considered as a whole grain.
Example grain structures from the simulation of grain coarsening.
Results of the simulation of grain coarsening.
Average grain area (in the number of cells, c) as a function of time (in the number of steps, cas) (a), and the rate of the grain coarsening as a function of 1/T (b).

The presence of certain elements namely, Cr, Zr, Li and high levels of Si in an aluminium alloy results in much coarser grains compared to grain size obtained in their absence on the addition of grain refiner.
Grain Refinement Studies: For grain refinement studies, Al-7Si alloy was prepared using commercial purity Al and Al-20%Si master alloy.
Eidhed, Fading mechanism of grain refinement of aluminium-silicon alloy with Al-Ti-B grain refiners, Mater.
Gruzleski, Mechanism of grain refinement in aluminium, Acta.
John, An analysis of relationship between grain size, solute content and the potency and number density of nucleant particles, Metall.

Forgings made from copper base alloys offer a number of advantages over products made by other processes.
Forgings made from copper base alloys offer a number of advantages over products made by other processes.
In die castings, shrinkage was found at the top of castings and numbers of gas holes were also found.
However, the grains in the area B had facets, but the grains in the area A hadn't.
Compared with the grains in same position of conventional forgings, the grains in semi solid forgings have different shape.

is the ordered number of nodes counting outward from the center?
Electroplating basement material is metal nickel (Ni); abrasive grain cluster is comprised of metal nickel (Ni) and CBN abrasive grain.
From Fig.3., Fig.4. and Fig.5., we known that the grain distribution and pore ration on the wheel surface can be changed by the changing of the phyllotactic parameters r, k, , so that the specific energy consumption, chip space, effective grind grain number and cooling fluid flow etc can be controlled when the workpiece is ground, specially, the leaves column line groove can be formed when the abrasive grain clusters are arranged based on phyllotactic pattern, cooling fluid can flow along the leave column line groove, so that the grinding heat damage is decreased and grinding scraps are removed quickly.
(a) Omitting abrasive grains, (b) omitting abrasive grain clusters, (c) the half-baked form of abrasive grain clusters, (d) rough electroplating coating . 600µm (b) Abrasive grain cluster 600µm (a) Grain Conclusions A superabrasive grinding wheel has been design based on the phyllotactic arrangement of sunflower seeds, and then the superabrasive grinding wheels with phyllotactic pattern are fabricated.
When the abrasive grain cluster radius is r=0.3～0.8mm, the changing of the abrasive grain cluster radius is small influencing to the developing of electroplating layer, electroplating processes influence the electroplating quality and the abrasive grain distribution within the abrasive grain cluster.

The grains of sintered tungsten exhibited growth, and grain size was determined by analyzing the areas of the spherical grains.
In Fig. 3(d), it can be seen that although grains have grown, the boundaries between grains are clear, and the bond between the grown grains is weak.
With increasing holding time, it becomes evident that sintered tungsten undergoes neck bonding between grains rather than localized grain bonding, resulting in the formation of interconnected grains.
However, temperatures exceeding 1600 ℃ led to excessive grain growth and a decline in strength, indicating grain coarsening and potential localized bonding.
Acknowledgements This work was supported by JST SPRING, Grant Number JPMJSP2132.

Brewer's grains is the main by-product of beer industry.
In this work, the waste brewer's grains has been modified through physical and chemical methods to generate suitable biosorption material.
The adsorption conditions was also studied so as to utilize the brewer's grains as the low cost material for Cr(VI) wastewater purification and the brewer's grains reutilization, then the results would be the theoretical basis for the comprehensive utilization of the material.
Material and Methods Reagents and instruments Preparation of modified brewer's grains biosorbent:The brewer's grains was from the bee laboratory in our school, washed with tap water, and broiled in 0.5 mol·L-1 sulfuric acid for 24 h.
And the 60-80 meshes of brewer's grains were selected in further experiments.

In the method, the fine-grained particles are subjected to partial melting and compacting.
Therefore, it is problematic to produce the ingots with fine-grained structure.
Therefore only a limited number of alloys having a wide solidus - liquidus range are used in these technologies.
As a result the granules with fine-grained structure (grain size ≈50 µm) or coarse-grained structure (grain size ≈350 µm) were formed correspondingly (Figure 1).
In the case of fine-grained granules the "reinforcement" possessed fine-grained structure.

A mathematical modelling of the testing situation is very valuable for a number of reasons.
The elastic properties of grains are anisotropic.
The number of points considered for DFT and IDFT are 1024.
Both and depend on the average grain size, single crystal elastic constants and orientation distribution of individual grains.
is the real wave number used in the analysis of the average isotropic homogeneous medium, and .