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The core is Co grains, while the shell is B4C/C compound.
Typical HRTEM images for the nanocapsules are presented in Fig.1(b), where the core of Co grains and the outer shell B4C/C are clearly distinguished.
With the formation of molten pool, a large number of Ar ions, C ions (ionized ethanol vapor) are into molten pool, the alloy is forced to evaporate.
First, the decrease of the particles size or grain size could reduce the intrinsic magnetic properties (such saturation magnetization, anisotropy, etc.) of the ferromagnetic material.
Microstructural analysis (XPS, XRD and HRTEM) showed that the particles have core-shell structure, with the core of Co grains and the shell of B4C/C composite.

The second factor is associated with random errors in intensity due to fluctuations in the number of reflecting grains, fluctuations of the primary beam intensity during a scanning time, and with an error in intensity definition because of the defocusing effect.
This results in reduction of a number of measured pole figures.
The essential contribution to the experimental errors in pole figures are the random errors in intensity due to fluctuation in the number of reflecting grains, caused by the limited X-ray irradiation area of a specimen surface and by the average size of a grain of a researched sample.
The given error is proportional to n1 , (where n is the number of reflecting grains).
Moreover, because of the finite dimensions of the tube focus, each given grain reflects a ray at an identical point, which is turned in a certain interval of the angles δα and δβ, i.e. the intensity measurements are correlated, although the identical grains reflect (for turns less than δα and δβ), the Poisson fluctuations of their number are not independent.

The aging treatment of 700°C for 24 hours which resulted in a change in morphology of the grains from skeletal to vermicular and promoted the formation of Ti-rich carbides on the grain boundaries.
Titanium diminishes grain boundary sensitivity at high temperatures due to the depletion of chromium carbides.
A large number of thermal stresses are produced during welding due to the localized heat near the weld region [7].
Finer grains are formed in the weld metal as compared to base metal because of the rapid cooling of the weld metal. 2.
It has the highest value in the weld metal because of the formation of finer grain in the weld metal. 4.

The matrix deposition on both surfaces of the SiC fibers and nanowires induced smaller matrix grains in the nanowire-reinforced composite, and thus a higher hardness and elastic modulus than the conventional one after an ion irradiation.
On the other hand, the SiC matrix grows from both surfaces of the SiC fibers and nanowires and there are more impingements of the growth fronts due to a larger number of deposition sites in the WA-CVI composite.
This leads to a smaller grain size of the SiC matrix in the WA-CVI composite than that of the conventional counterpart as shown in Fig. 3.
Our supplementary irradiation studies on a single crystal SiC and CVD SiCs with various grain sizes suggest that a small-grained SiC has a higher resistance to an amorphization [5].
The matrix deposition from both surfaces of the SiC fibers and nanowires induced smaller matrix grains in the WA-CVI composite, and thus a higher hardness and elastic modulus than the conventional one after an ion irradiation.

Microstructure observation revealed that the grain sizes of the composites increased with increasing solution temperature and decreased with more severe deformation.
It can be seen that the grain sizes increases with increasing solution temperatures.
It can be seen that the microstructure under different solution temperatures are of equiaxed grain of different sizes, and that the grain sizes increases with increasing solution temperatures.
By compare Fig.2 with Fig.3, we can saw that grain sizes decreased with increasing deformation strains under the same temperatures.
Acknowledgement It is a project supported by natural science foundation of shanxi province China (project number: 2011011021-1).

The regions critical for the performances of the weld are the coarse-grained heat affected zone and the fusion line.
Obviously, the austenite grain size without buttering is larger than the austenite grain size with buttering in the weld metal.
The HAZ and austenite grain size are attributed to the heat input and cooling rate.
A high-heat input provides enough time for the grain to grow more extensively in the fusion zone and the HAZ, respectively
Vickers hardness number along DMW with (a) Non-buttering and (b) Buttering Figure 7 shows that the hardness profile for DMW with buttering is not too slanted in comparing with the hardness profile of DMW without buttering.

The surface morphology of die cast Al alloy depicts the dendritic structures and spray formed Al alloy contains the equiaxed grains, coarse grains and fine grains across the surface.
Surface morphology of Al alloy produced by spray forming technique shown in Fig. 6(b) recorded that equiaxed grains, fine grains, coarse grains and porosity.
The effect of reduced in cooling rate and spray deposition in the formation of Al alloy produces the equiaxed grains and fine grains in the compact.
The wear debris of spray formed Al alloy contains large number of smaller flakes in contrast to wear debris of die cast Al alloy.
The microstructure of die cast Al alloy depicts the dendritic structures and spray formed Al alloy depicts the equiaxed grains, fine and coarse grains.

However, pernicious stray grain formation often occurs.
Multi-Scale Mathematical Model Procedure (1) Heat transfer model Significant difference of crystallization-independent shape of solid/liquid interface is attributed to a number of combinations of laser power and welding speed through thorough steady-state Rosenthal heat flow solution.
(1) where Γ is the Gibbs-Thomson coefficient, R is the dendrite tip radius, Pei is the Peclet number for i, mi is the liquidus slope, C0,i is the initial concentration for i, ki is the partition coefficient for i, ζc(Pei) is a function of the Peclet number, Iv(Pei) is the Ivantsov solution and Ghkl is the average temperature gradient near dendrite tip
Axis-symmetrical growth kinetics attenuate dendrite tip undercooling to counterbalance nucleation and subsequent growth of stray grain formation.
Numerical analysis of stray grain formation during laser welding nickel-based single-crystal superalloy part II: multicomponent dendrite growth.

It was found that the Mg-Zr alloys homogenized at 500℃ and annealed at 350℃ contained a fine dispersion of Zr-containing particles at grain boundaries and within grains.
The Mg-0.4Zr alloy homogenized at 500 ℃ for 8 h followed by annealing at 350℃ contained a dispersion of Zr-containing particles at Mg grain boundaries and within the Mn grains.
Small particles along grains and dendrite boundaries in the as-cast Mg-0.6Mn alloy were almost fully dissolved into the Mg solid solution during solution treatment at the temperature of 550 ℃ for 8 h, as shown in Fig3b and 3c.
After annealing at 300℃, without solution treatment (T5), a large number of rod-like particles, 30 to 100nm in length, precipitated at annealing times of 10h (see Fig.6b).

SEM photographs show that the nanocrystalline diamond films consist of unfaceted diamond grains.
Further investigation using AFM reveal that the average size of the grains is 50-100 nm.
Journal Title and Volume Number (to be inserted by the publisher) 89 Raman scattering is 50-60 times higher for sp 2-bonded carbon compared to sp 3-bonded carbon, hence the diamond component dominates in films.
We can see two sets of lattice fringes distinctly inside the grain.
These films appear very smooth, homogeneous, with a fine-grained morphology.