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Grain-oriented Bi4Ti2.92Nb0.08O12 (BITN) ceramics were prepared by hot-forging (HF) method.
In this study, grain-oriented Bi4Ti2.92Nb0.08O12 (BITN) ceramics were selected to confirm our concept as the first trial, because of its high Tc and ease of preparation of grain-oriented ceramics by hot-forging (HF) method.
Grain-oriented samples were prepared by the hot-forging (HF) method [5].
The grain-oriented factor, F, was calculated using the Lotgering method [10].
X-ray diffraction pattern for OF-BITN ceramic shows a single phase of bismuth layer-structured compounds with the layer number, m=3.

It was concluded that this was due to the interaction of grain refiner particles with the bridge formation mechanism observed in non-grain refined melts.
This recycled metal had of course already been inoculated with TiB grain refiner.
A reduced efficiency of the CFF may have resulted due to the presence of these grain refiner particles in the melt.
This in turn would have increased the number of inclusions entering the bed filter.
Stirring of the melt in the furnace increased the total number of inclusions as well as the number of larger inclusions reaching the filter from the furnace.

Corrosion resistance of Si and Al-bearing ultrafine grained weathering steel T.
The ultrafine grained (UFG) weathering steel containing Si and Al showed higher corrosion resistance than carbon steel in the test.
Moreover, the principle of increasing the strength of steels by the grain refinement was shown in our 1 st project.
As the surface rust increased with the number of test cycles, Rh increased.
Fig.7 shows the results of EIS parameters on Al and Si-bearing UFG weathering steel and SM conducted after the corrosion test, showing Rrust and Rt against number of cycles.

After 4 passes the grain size was reduced to ~200 nm, and in this range twins are mainly nucleated at the grain boundaries [14].
The larger the number of ECAP passes, the faster the hardness reduction for 4N5 purity samples (see Fig. 2c).
Microhardness as a function of storage time for 4N5 (c) and 4N (d) purity samples processed by different numbers of ECAP passes.
(a) DSC thermograms obtained at a heating rate of 10 K/min for 4N5 and 4N purity Ag processed by different numbers of passes.
As in UFG microstructures twins mainly form at grain-boundaries, the impurity segregation in the boundaries yielded lower twin boundary frequency in 4N purity samples compared to 4N5 purity counterparts for large number of ECAP passes. 2.

Peculiarity of Grain Boundary Diffusion of FE and CO in CU Khairullin Ainur1,a, Nikulkina Valeriya1,b, Zhevnenko Sergei1,c, Rodin Alexey1,d 1Department of Physical Chemistry, NUST MISiS, 4, Leninsky pr-t, Moscow, 119049, Russia aaika-88@inbox.ru, bfeba-3@ya.ru, czhevnenko@misis.ru, drodin@misis.ru Keywords: grain boundary diffusion, grain boundary segregation.
In this article new experimental evidences of anomalous grain boundary diffusion (GBD) of Fe and Co in Cu were describe.
Introduction Copper is a metal where bulk and grain boundary diffusion were studied carefully by many authors [1] and may be for the largest number of different elements.
Concentration profiles were measured by X-ray microprobe along the GB and in the grain bulk far from GB.
Kozma: Handbook of Grain and Interphase Boundary Diffusion Data, Ziegler Press, Stuttgart (1989) [2] L.

With a large sampling space fewer peaks are counted as representing a grain as illustrated in Fig sampling space (ssopt) suggested by Blunt and Ebdon [ fulfil the relationship given in Eq spacing would consider each grain to have a number of peaks that are in actual fact cutting edges on the same grain.
A smaller sampling spacing would consider each grain to have a number of peaks that are in actual fact cutting edges on rain.
The optimum for measuring the number of grains should is the stated grit size in microns.
Both wheel 1 and 2 experience a drop in the number of summits (Sds) present which reiterates the view that the grains are fracturing or are being pulled out.
The parameter Sds has been shown to provide information on the overall reduction in the number of grains while Ssc has hinted that for some wheels the grains are self-sharpening.

Hence it can be considered that the number of potential barrier, which is inversely proportional to the grain diameter, eventually changes with the amount of aluminum addition.
Tilt angle of the grains, that is angle made by the [ 0011 ] of the both grains, is ranged between 13 and 16.5° in this grain boundary.
In addition, segregation of aluminum at grain boundary was also observed at incoherent grain boundary as shown in Fig.3.
(1) Here, e is the electric charge, Ns density of trap at grain boundary, ε relative dielectric constant, ε0 the dielectric constant in vacuum, n carrier concentration in grain, vn thermal velocity of the electron, L length of specimen, V applied voltage to the specimen, ng the number of grain boundary along L, k the Boltzmann constant, and T absolute temperature [7].
Because the grain boundary plays an important role in the variation in mobility, grain boundary structure was modified via magnetic texturing which enabled to align c-axes of grains highly.

The unrefined base alloy is comprised of large, dendritic grains with the average grain size of 180m, as shown in Fig 1(a).
The refined alloy still exhibits small equiaxed grains and maintains the grain size level at 40 m.
Based on the above analysis, the superior stability of the fine grains in the base alloy with Al addition stems from the grain growth restriction provided by the large number of 'inactive' Al2Y particles together with the unknown Mg-Al-Y particles along the grain boundaries.
In addition, these grain boundary particles also suppress grain boundary sliding, which compensates the reduction of creep resistance owing to the grain refinement.
Discussion The inoculation in both cast Mg alloys produces a large number of inactive Al2Y particles, but the particle distribution may be different.

The EN AW-2017A alloy consists of a grains and the Al2Cu phase.
Between large elongated grains are also visible cluster very small equiaxed α phase grains in the system band.
At the same time, the number of load cycles N was recorded.
In many cases, they are generated at the grain boundary of the solid solution.
Fatigue crack length „a” versus number of cycles N (active side specimen).

The Microstructure was mainly composed of granular bainite(GB) and a small number of lath bainite ferrite (LBF) as shown in Fig. 1.
The microstructure of CGHAZ (Tp1 is 1320 ˚C) is dominated by coarse lath bainite and granular bainite, and the grain boundary of original austenite is clear; in the austenite grain, the original grain is divided into different regions by lath bundles with different directions.
After the peak temperature of the second thermal cycle in 650 ˚C, the structure of the coarse grain zone experiences the tempering process associated with carbon precipitation, M-A decomposition, the number of granular bainite increasing and bainite bundles roughening.
A large number of blocky M-A is mainly distributed at the grain boundary (Fig. 3(c)).
Acknowledgements This work was financially supported by the National Natural Science Foundation of China Youth Found (grant number 51401112) References