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The brittleness of high silicon steels is related to ordered phases, grain size, impurity on grain boundary and etc.
Grain size was about 70 µm in the sample atomized by N2 gas, while above 600 µm in the samples atomized by Ar gas.
It appears that no grain grow growth took place in the sample atomized by N2 gas, considering that the average diameter of the powder taken from cyclone was around 50 µm.
In the sample atomized by N2 gas, a number of gas pores were observed and the nitrogen content analyzed by N2/O2 determinator reached 0.01~0.02%.

This is because the plume may contain quite a number of oxygen atoms and ions which can react with silicon, leading to the formation of an amorphous silicon oxide layer on the substrate Fig. 1 Geometries of the interdigital electrodes: finger length l = 925 µm, finger width 2s = 5 µm and finger spacing 2g = 3 µm.
The average grain size was estimated to be ~ 30 nm in diameter.
Moreover, the film also contains a noticeable amount of misoriented grains.
Most of these misoriented grains nucleated at the middle of the film which could be caused by the defects generated during the grain growth.

The FTIR spectra in the wave number range from 400 to 4000 cm−1, were obtained by the KBr pellet technique.
The grain size is found to be affected severely by the calcination temperature, i.e. higher temperature resulted in bigger average grain size.
The image of the sample calcined at 1000 °C (Fig. 5a) indicate the presence of spherical particles with grain size lower than 100 nm, forming characteristic chains due to the beginning of sintering.
The sample at 1300 °C (Fig. 5b) indicates the further sintering of the grains forming larger particles.

Upon refining the microstructure, a lot of new crystallites and grain boundaries evolve, which may act as fast diffusion paths for hydrogen absorption [10].
The benefaction of Mn substitution on the hydrogen absorption capacity and kinetics of the alloy are attributed to the increased cell volume and the refined grain rendered by Mn substitution.
The enlargement in the cell volume is highly beneficial to the hydrogen absorption capacity, since, the grain boundary possesses the capability of the largest hydrogen absorption [11].
It has been already reported that the high surface to volume ratios (high specific surface area) and the existence of large number of grain boundaries in nanocrystalline alloys enhance the kinetics of hydrogen absorption/desorption [5].

The number of Cu pieces can be changed to adjust the content of Cu in the films.
From the comparison, we deduced that ZnO doped with a moderate of Cu atoms might reinforce the grain growth along the c-axis, while excessive Cu dopant might degrade the grain growth along the c-axis.
XRD and Raman analysis showed that ZnO doped with a moderate of Cu atoms might reinforce the grain growth, while excessive Cu dopant might degrade the grain growth.

The activation energy for atomic diffusion at the surface, interface and grain boundaries is relatively low compared to the bulk diffusion due to a looser bond of the atoms and higher oscillation frequency of the diffusing atom.
This enhances the atomic diffusion, and thus eases the diffusion bonding of two metal pieces assuming that a perfect interface contact exists The interface contact can be optimized by a treatment of the surface to be bonded through a number of processes, such as mechanical machining and polishing, etching, cleaning, coating, and material creeping under high temperature and loading.
The yTiA1 alloy after HIP and heat treatment at 673 K for 1 h exhibits a near y microstructure, with some α particles or lamellar colonies at grain boundaries.
In contrast to Zone 1, the net diffusion fluxes of Al and Ti atoms in Zone 2 cause both its enrichment in α and depletion in Ti, leading to the nucleation of the α2 phase in the original α-Ti grain structure.
In the bonding process, the diffusion of Ti atoms in interface is mainly controlled by grain boundary diffusion. 4.

As shown in Fig. 2, the Y- intercept is 0.0027 taking λ as 0.154 nm, the grain size was found to be around 62 nm.
The small variation in the size of grains calculated by Debye-Scherrer and W-H method was due to the fact that in Debye-Scherrer formula strain component was assumed to be zero and the diffraction peak broadening was assumed to be due to reduced grain size only.
The SEM image reveals that the YPO4:Eu3+ nanophosphor was nearly a number of cobblestone spherical particles with agglomeration and grain size less than 100 nm.

This is evidently implied that in this material, the existence of grain boundaries has no effect on the occurrence of 2-R transformation.
It may be due to there is no difference on nucleation rate of Ti3Ni4 precipitation between grain boundary (IGB) and grain interior (IGI).
%Ni as a Ni-rich alloy has low IGB/IGI, therefore the preferential precipitation in the grain boundary region becomes less effective, so high-Ni content favours the tendency for homogeneous precipitation across the whole sample.
Acknowledgements This research funded by Ministry of Education Malaysia and Universiti Teknologi Malaysia under Fundamental Research Grant Scheme, vot number RJ1300007824.4F210.

The higher magnification image shown in Fig. 1 (c) and Fig. 1 (d) indicated that sintered grain boundary and occurred small pore between grain boundaries size about 1 mm. 1 CM (a) BVF (before coated) (b) BVF at ´35 (c) BVF at ´1000 (d) BVF at ´2500 (e) BVF at ´35 (after coated) (f) BVF at ´1000 (after coated) (g) BVF at ´2500 (after coated) Fig. 1.
(a)-(g) SEM microstructures of BVF (before and after coated RS gel) However, after coated with RS gel, a layer of gel was coated on surface of grain boundary and inner pore walls of BVFs (Fig. 1(e)-(g).
In humans, glucose was the primary source of energy, and was critical for normal function in number of tissues.
However, after heat at 1250°C for 3h of sample of BVF, the sharp peaks of HA phase increased due to forming high crystalline of grain (Fig. 2(c)).

Introduction At the present, the sever plastic deformation (SPD) techniques are starting to emerge from laboratory scale research and to gain increasing appreciation and understanding for the potential commercial applications of various ultrafine-grained (UFG) materials [1-5].
The values after HPT tests Alloy Sample thickness [μm] Number of rotation Maximum εvon Mises [%] Maximum σvon Mises [MPa] di df Ti29Nb13Ta 1200 940 1 15,4521 2507,2243 Ti29Nb13Ta 1270 960 2 31,2680 2573,2197 Ti29Nb13Ta-5In 970 790 1 18,3309 1660,8036 Ti29Nb13Ta-5In 870 780 2 36,9458 1682,6421 Ti29Nb13Ta-5Ag 990 805 1 17,9292 1677,2425 Ti29Nb13Ta-5Ag 1010 800 2 36,0282 1694,4013 Ti29Nb13Ta-5Cr 970 830 1 17,9370 2175,2076 Ti29Nb13Ta-5Cr 990 825 2 34,9364 2252,4821 Ti29Nb13Ta-5Zr 990 810 1 17,8007 1619,8865 Ti29Nb13Ta-5Zr 990 805 2 35,8164 1660,0837 The curves of yield stress as function of the strain are presented in figure 4.
Processing by High Pressure Torsion (HPT) is effective in producing exceptional grain refinement in β titanium alloys.
Zhu, Continuous processing of ultrafine grained Al by ECAP–Conform, Materials Science Engineering: A, 382 (2004), 30-34
Langdon, Experimental parameters influencing grain refinement and microstructural evolution during high-pressure torsion, Acta Materialia, 51 (2003) 753-765