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Type-A precipitate was found at only grain boundary. 1.
Greater number densities of this precipitate and the parallelogram type precipitate are distributed at underaging stage.
Therefore, course precipitate observed in grain boundary regions.
But no Ag was detected in Type-A precipitates on grain boundary of ex.
Type-A precipitate appeared on grain boundaries.

The morphology of strengthening phase β-Ni3Si is graininess distributing on the grain boundary.
It is observed that the morphology of β-Ni3Si is graininess distributing on the grain boundary.
When the solid solution treatment process is 850˚C holding for 2h, the grains of NCu30-4-2-1 alloy is fine and a large number of needle-like (α+β) eutectics (the black structure) still exist in the matrix (Fig.3a).
Further rise of solution temperature to 1050˚C, the phenomenon of the abnormal growth of grains is occurred (Fig.3c).
The morphology of strengthening phase β-Ni3Si is graininess distributing on the grain boundary

The 2nd International Conference on Recrystallization and Grain Growth follows on from: • the 1 st joint Conference on Recrystallization and Grain Growth in Aachen 2001 and • two series of international meetings on the topics of recrystallization and grain growth, i.e
These series of conferences, starting in the early 90's, correspond to a renewed interest in the mechanisms and modelling of recrystallization and grain growth for a variety of reasons.
In both cases it is increasingly important to master the grain sizes and/or orientations by close composition/processing control.
One of the themes of the present conference is how to cover the entire set of reactions governing recrystallization and grain growth during industrial processing - termed through process modelling.
There are also a number papers dealing with new techniques such as laser ultrasonics and high energy X ray methods of characterizing deformation structures, recrystallization and grain growth during (in-situ) heat treatment.

This study aimed, with the aid of analysis of variance (ANOVA), to investigate and quantify the influence of moisture ranging between 12% and over 30% (fiber saturation) on the mechanical properties: strength and modulus of elasticity in compression and in tension parallel to grain; modulus of rupture and modulus of elasticity in static bending; shear strength parallel to grain considering wood species Ipê (Tabebuia sp) and Angelim Araroba (Vataireopsis araroba).
Properties considered were strength (fc0) and modulus of elasticity (Ec0) in compression parallel to grain; strength (ft0) and modulus of elasticity (Et0) in tension parallel to grain; modulus of rupture (fm) and modulus of elasticity (Em) in static bending; shear strength parallel to grain (fv0).
Table 1 shows the number of specimens obtained by species, type of test and moisture content, totalizing 400 samples and 750 determinations.
Table 1 Number of specimens used by wood species and type of test.

In recent years, there has been interested in the use of equal-channel angular pressing (ECAP) technique to obtain ultrafine-grained materials.
After ECAP, the Al2Cu particles are markedly refined and the number of Al2Cu particles tend to decrease with ECAP passes.
The supersaturated solid solution was generated by ECAP and equiaxed θ phase grains precipitate at grain boundaries by re-aging treatment.
It is generally agreed that the microstructure of an aged Al-Cu alloy has a three-phase system that contains with θ phase, α-Al matrix and Cu depleted zone in the surroundings of θ phase, and the Cu depleted zone along grain boundaries is the anode, whilst the grain bodies and the intermetallic Al2Cu are cathodes [16].
On the other hand in the Al-5 wt% Cu alloy samples after ECAP, the number of corrosion pits decreased and sizes became smaller with increasing ECAP passes.

The method of thermal annealing of ZnO films has been performed on a number of experimental conditions, showing an improvement in film quality.
This increase indicates that the number of atoms sputtered from the target is proportional to the power.
It is found that with the increase of sputtering power, the grain size of the ZnO film increases first and then decreases and the maximum grain size corresponds to the sputtring power of 50 W The root mean square (RMS) roughness of ZnO film fabricated at 50 W is 0.9 nm.
Table 1 shows the grain size of ZnO fabricated by different sputtering power.
The grain size firstly increases, and then decreases and the maximum grain size corresponds to the sputtring power of 50 W, which is consistent with the AFM results.

From the FESEM images (a~d), the MCN thin films are crack-free and compact, with grain size ranging 20~240nm.
From the images, in addition, it can be seen that the grain size of films increase with increase in annealing temperature (Ta).
Smaller grain size of the thin film leads to large number of insulating grain boundaries, which results in higher resistivity, due to the increased energy barrier for electron conduction [15-16].
In this paper, it can be seen that the grain size of the thin film Mn1.74Co0.72Ni0.54O4 increase with the increasing annealing temperatures, meanwhile, below the temperature of 750℃, larger grain size results in small number of grain boundaries, which implies scattering centers for the flow of electrons, then decreases the resistance.
The FESEM images of surface morphology show that the grain size of films increased with increasing annealing temperature.

This type of spring must withstand numerous numbers of compressive and tensile loading cycles before it can fail, or never fail at all during the service period [1].
The grain boundary also shows different in term of size but not very significant.
Size of the grain boundary for both samples was different along with the phase that present.
Grain size shown in non-failure area was smaller than the failure area.
It is important to have smaller grain size in steel.

These results are believed to be attributed to a grain size effect.
These grains will be called 'island grains' because they are surrounded by recrystallized areas.
In this approach 'island grains' are deformed grains for which the distance between precipitates all around the boundary is too small for re-nucleation to occur.
The amplitude of excess losses is strongly related to the number of moving MOs, this parameter depending on microstructure too.
If grain size effect is extensively described in literature dislocations and misorientation between grains effects on magnetic losses have not been much studied.

The consolidated composite consists of 10wt.% B4C, 50wt.% coarse grain 5083 Al and the balance nanocrystalline 5083 Al.
This can be thought that it is mainly because a large number of other atoms (such as Mg) have dissolved and changed the crystalline grain constant firmly.
Optimization of strength and ductility in nanocrystalline and ultrafine grained metals.
Instabilities and ductility of nanocrystalline and ultrafine-grained metals  Scripta Mater 49(2003), p. 663
Al–Mg alloy engineered with bimodal grain size for high strength and increased ductility.