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The traces of grain boundaries were parallel to the ED and TD.
Despite the texture of the initial state was dominated by cube-oriented grains, the grains with orientation forming copper-type texture are also well-marked.
For both metals the development of deformation microstructure and texture as a function of the number of passes was analysed using the SEM/EBSD system on the ND/ED and ND/TD sections.
(i) The number of applied passes had a strong impact on the global deformation behaviour and on the intensity of grain refinement.
Two types of boundaries between the grains are observed in the present copper and AA1050 alloy samples: the boundaries that separate the grains placed inside a particular layer and the boundaries between the grains of adjacent layers.

It reduced the residual glass phase, and increased the number and the length diameter ratio of β-Sialon grains [7].
When fine-grained material had the large proportion of grain boundaries and damaged along the grain boundary, crack propagation took a roundabout way.
Therefore, the z=1of β-Sialon grain was significantly more slender than the z=3 of β-Sialon grain.
The material appeared a large number of pores, and the relative density decreased.
The coordination number of B atoms, N atoms were 4, and the lattice constant was 3.615 Å.

For 800 ℃, the equiaxial recrystallized grains were obtained.
The number of recrystallization nucleus increased for annealing at 700℃(Fig.4(e)).
In fact, recrystallization grain nucleated on the boundary of grains at 660℃.
Of course, long held time led to other grains recrystallize.
The number of recrystallization nucleus increased for annealing at 700℃.

Therefore, due to the significant disordered grain boundary regions, nc-materials are thermally unstable and are subjected to a strong driving force for grain growth.
Equiaxed grains were usually found in consolidated nc-Cu and nc-Ni while grains were usually crystallized along specific direction in electrodeposited nc-Ni and nc-Cu.
But the average grain size of the as-prepared specimens is about 100 nm.
However, the melting point is lower than that of coarse-grained aluminium by 14 K.
The reasons are that: firstly, the adsorbed gas can be desorbed easily when the nano-particles are heated; the number of micro-pores became less.

Estimation Model Since MnZn soft ferrite is a kind of polycrystalline material composed of a great number of grains, the eddy-current losses of single grains in the micro-structure of this material are calculated, and then the eddy-current loss per unit volume of the core is deduced.
Generally, the grains of MnZn ferrite are polyhedrons, but the simplified model in this paper simplifies the grains as spheres.
If the mean radius of the grain (sphere) is, then the time-varying eddy-current loss of a grain, can be found by , (5) in which the grains per unit volume, excluding the grain boundary, is [12].
In this figure, , and represent grain resistance, grain-boundary resistance and grain-boundary capacitance, respectively.
Grain-boundary resistance dominates the impedance of the sample at low frequencies, while grain resistance dominates at high frequencies.

It can be found that, small-size (< 10 nm) grains, together with pores in grain boundaries, aggregate at the boundaries of larger grains.
Moreover, pores in grain are easy to be observed.
For nano-grained polycrystalline ceramic, both lower grain scattering and lower pore scattering result in high Fig. 3.
However, for nano-grained polycrystalline ceramic, both lower grain scattering and lower pore scattering result in high transparency..
Acknowledgements This work was supported by NSFC of P.R.China under grant number 50272040, Fok Ying Tong Education Foundation under grant number 91046, and Youth Science and Technology Foundation of Sichuan Province under grant number 03ZQ026-039.

The size of crystalline grain was minished and elongated, equiaxial grain was elongated and staved along the rolling direction.
When the deformation exceeded 64.26%, non-equiaxed grain was more and more severity [5], the grain was stretched heavily and further refined and warping.
The grain was elongated remarkably along the rolling direction and began putting up to a trend of crack when the deformation was 43.71%, a mass of ferrite grain was distorted and refined with deformation increasing, the grain boundary was hard to discern.
Form the fig.3(c) known that cold deformation leaded to a large number of dislocation in intracrystalline, the augment of dislocation density was heavily because of dislocation multiplication with deformation increment.
The grain was elongated and refined with the deformation increasing, and to a certainly deform, the grain was warped and broken, it was formed the deformation texture

A number of voids are found in the tensile fracture surfaces when the welding temperature is below 1100oC.
The grains of 40Cr steel grow obviously when the welding temperature is higher than 1100oC.
The volume of the ferrite with coarse grains in the side of 40Cr increases significantly, and the depth is about 300 microns, indicating that the carbon diffusion from 40Cr to Cr12MoV occurs in welding.
A large number of hollows can be found in the fracture surface of samples in tensile test when the welding temperature is below 1100oC.
The grains of 40Cr steel grow conspicuously when the welding temperature is higher than 1100oC.

Influence of finishing rolling variables on the austenite recrystallization and grain growth V.
The role of grain size and precipitation on final mechanical properties was discussed based on different strengthening mechanisms.
This paper seeks to address the influence of finishing rolling variables on the Nb precipitation state and its control on austenite recrystallization and grain growth.
The Nb precipitates retard or even suppresses austenite recrystallization leading to a pancake microstructure which offers a larger number of ferrite nucleation sites.
Fig. 1 Comparison between the grain sizes obtained after routes 1, 2, 3 and 4.

These excellent properties are resulted from the grain size reduction and the existence of large numbers of grain boundaries in the microstructure [1].
The grains are large and tend to agglomerate.
For CoFe nanocrystalline coating prepared at 90 minutes deposition, the small grain size is due to the existence of higher number of interfaces such as grain boundaries in the coating microstructure.
The higher proportion of boundary atoms in the grain boundaries compared to those inside the grains has cause the grain size reduction in CoFe coating.
The grain size reduction has resulted in the high volume fraction of the boundary atoms inside the grain boundaries.