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Analyzing the experimental results, most of pinning points located in the grain boundary in ferromagnetic materials.
When the domain wall moves from one pinning point to another, the domain wall can be consider to crossing a grain.
This is because most of pinning points in the ferromagnetic materials are at the grain boundaries.
When the domain wall moves from one pinning point to another, the domain wall can be consider to crossing a grain.
After normalizing, the grain becomes thinner and the released MBN correspondingly reduces.

The first hypothesis deals with the preferential development in the deformed matrix of grains with specific orientations.
The second one supposes that nuclei in particular crystallographic relation with the neighboring grains grow preferentially.
Recently, a large number of experimental studies combine local orientation determination (within the Scanning Electron Microscope through Electron Back Scattered Diffraction or within the Transmission Electron Microscope) and macroscopic texture analysis [8-10].
It is suppose that the <112> fiber is obtained by abnormal grain growth [20], but it has not been experimentally proved at this time.
The results obtained are usually discussed in relation with the activation energy of grain boundary self-diffusion (GBSD).

Without the front ceramic plate, which is the main protection in a MAS [11], a rather large number (20-50) of aramid fabric plies would be required for protection against a relatively high energy projectile [6].
It is important to mention that, upon sintering the Nb2O5 reacts with Al2O3 and forms AlNbO4 precipitates in the grain boundaries.
The size of the fragments in Fig. 4 coincides with that of the average grain size, 3 µm, of the original ceramic in Table 1.
With greater magnification, Fig. 4(b), one might notice the faceted polyhedral aspect of the fragments, which is typical of a grain morphology.
Addition of 4 wt% of Nb2O5 to the Al2O3 produces AlNbO4 precipitates that cause grain boundary embrittlement.

In recent years, Srn+1TinO3n+1 and Can+1TinO3n+1 homologous compounds with n indicates the number of layers of SrTiO3 and CaTiO3 have been widely applied as microwave passive components because they have excellent microwave dielectric properties [6,7].
Moreover, the porosity decreased with increasing sintering temperature and time owing to grain growth.
After reaching the maximum at x=0.06 for 4 h, it slightly decreased owing to the rapid grain growth.
On the other hand, extrinsic losses are produced by a second phase, grain sizes, and densification.
However, the decrease in Q´f value at high x contents was due to the rapid grain growth as observed in Fig. 3.

The phase evolution of Li(Ni0.8Co0.2)O2 was confirmed by X-ray diffraction and the grain size and morphology of the surface were analyzed by scanning electron microscopy and atomic force microscopy.
The amount of Li evaporation was controlled by the number of Li foils, each Li foil has 60㎛ thickness.
The LiNi0.8Co0.2O2 phase evolution was confirmed by X-ray diffraction and microstructural characteristics such as grain size and surface morphology were observed by scanning electron microscopy (SEM).
This result can be considered as Li-diffusion and the reaction between lithium and textured Ni-Co tape was accelerated by the textured channel rather than random-oriented grains during heat-treatment for LiNi0.8Co0.2O2 phase formation.
Also, LiNi0.8Co0.2O2 composite phase showed spherical particle with interconnected porous morphology, and its grain size was about 400~500 nm.

During the operation of the demonstration plant at Trombay, a number of leaks were detected near the weld joints of dissolver made of AISI type 347 due to knife line attack.
Corrosion problems have been experienced with dissolver due to knife line attack at weld regions, and end grain attack at pipe cut sections.
Unlike sulphur, phosphorus does not form any compound, however segregates at the grain boundaries and leads to selective corrosion attack along grain boundaries [13,14].
However, it forms dichromium boride (D-Cr2B) along grain boundaries even during water quenching after solution annealing.
Nitrogen is a more effective solid solution strengthener than carbon and also enhances grain size strengthening.

The microstructure of the particular ceramic with full density confirmed that the particle grain in ceramic block have shaped with the less pore and connected thickly.
From the whole view, the grains remained remarkably small (0.5 um) and in homogeneous distribution.
Acknowledges This work is supported by Shanghai Leading Academic Discipline Project (Project Number: J51504) and Foundation of Shanghai Institute of Technology (No.YJ2011-30).

These maintenance intervals are determined by the number of thermal excursion cycles (for components limited by low cycle fatigue) and/or operating time (for components limited by creep).
(c) Eventually the grain boundary ductility shortfall in high strength blade alloys was solved by an unexpected processing breakthrough: directional casting solidification that virtually eliminated grain boundaries in the principal stress direction
A number of improvements have been made over the years to alloy 718 in melting, ingot conversion, forging, and heat treatment.
It can produce a uniform distribution of fine grains with high density.
However, consideration should be given to reducing their frequency by improved process control since the upper limit on acceptable number of defects may not be precisely known.

The parts of the scale which have tendency for spalling showed bigger, pyramidal grains and laminar porous structure (Fig. 1d).
Unspalling scale presented smaller grain size and much denser packing.
These scales can be partially relaxed due to creep processes if the oxide thickness is small and the grains small [10, 11].
The results of average numbers for as-clad layer and after oxidations are showed on the fig. 6.
Osgerby, Oxide scale damage and spallation in P92 martensitic steel; Materials at High Temperatures, Volume 17, Number 2, May 2000 , 307-310

To reveal the formation mechanisms of the ASBs, they carried out a microstructural analysis with the aid of the transmission electron microscopy (TEM), and found that a deformed ASB does not have a clear boundary with its surrounding material, but that the material grains inside the band was elongated along the shear direction through a large plastic deformation.
The deformed ASBs were developed by the accumulation of a great number of mobile dislocations in the primary shear zone.
A transformed ASB, on the other hand, has obvious microstructural boundaries, containing a band core with a much refined grain structure (Fig.3) and a transition zone with elongated grains (Fig.4) in the shear direction.
Fig. 4 Grains elongation in the transition zone from the core to parent material of a transformed ASB [1].
However, the above experimental analysis is limited to a few number of cutting conditions, which is insufficient for optimizing an HSC.