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Up to now, a number of high damping alloys such as Mn-Cu and Fe-Cr have been developed and successfully applied in ship and railroad industries [3, 4].
Further increasing Nb content to more than 1%, large amounts of white particles with irregular morphology present and most of them are distributed along the grain boundaries.
(ii) A number of particles with various sizes are randomly distributed inside the ε martensite, at the ε martensitic variants boundaries and γ/ε interfaces.
Shin et al. [30] found that, in Fe-17Mn, the ultra-fine grained sample containing a low volume fraction of ε martensite possesses a damping capacity comparable to that of the coarse-grained sample with a high ε martensite fraction.
De Cooman, The effect of grain size on the damping capacity of Fe-17 wt%Mn, Mater.

Great emphasis is placed on the study of protection against sulphate corrosion and there are a big number of studies focused on predicting its course [7], [8], [9], [10].
At the same time, a number of studies are focused on slowing down degradation by partial substitution of suitable additives and secondary raw materials for Portland cement [12], [13].
As for FBC fly ash, fly ash particles do not melt, grains remain porous, their structure is layered and they have a large specific surface area.
Waste foundry sand contains grains of fraction which are smaller than 4 μm and they are used as microfiller.
Recommended replacement rate for fine grain fractions is in the range of 20–30% [25].

After a long research for building " big " high purity Ge spectrometers, we have recorded, starting from 30 years ago, strong efforts for materials like CdTe, which only now is really commercial; 10 years ago, epitaxial GaAs and even more recently SiC came into play for other kinds of application, since for gamma ray spectroscopy their atomic numbers were too low.
Polycrystalline materials like CVD diamond displayed in the past non-uniform cce maps, in which it was easy to notice the appearance of single grains.
Moreover, the presence of traps in the defective regions around the grain boundaries caused strong polarization effects which in practice impeded in many cases to get reasonable cce maps.
Even after a priming of 10 Gy of X-rays the sample showed polarization effects in times of the order of few minutes: cce distribution was quite non-uniform, displaying the morphology of grains according to their local values of cce and, moreover, energy resolution was extremely bad, since the multichannel pulse spectrum - displayed at bottom right - showed a very broad band.
The number of events above the threshold also decays from 573 to 506, i. e. of about 11 %.

Results showed that with increasing Si content martensite got coarsening and the number and content of primary carbide increased; The type of primary carbide was M7C3 and Si mainly dissolved into martensite by XRD analysis; The wear resistance was effectively improved while Si content increased.
It can be seen from the Fig. 3 that carbide grain size was less than 1µm and distributed homogeneously which is helpful to improve the wear resistance when the content of silicon ranged from 1.0% to 2.0%.
Table 2 presented the percentage by weight of carbides extracted from the structure of the specimens and the type of carbides in the structure is shown in the Fig. 4.: Table 2 Effect of silicon content on the percentage of carbides(wt%) Specimen Number 1 2 3 Mass Percentage of carbides 4.23 5.38 5.97 The mass percentage of carbides extracted from the specimens during the same heat treatment was increasing when the content of silicon ranged from 1.0% to 2.0%, as shown in Table 2.
Table 3 The wear volume loss and relative wearability of specimens Specimen Number Wear volume loss V/mm3 Relative wearabilityε 1 0.1103 1 2 0.0679 1.62 3 0.0575 1.92 Table 3 showed the effect of silicon content on the wear resistant of the samples.

This stabilization effect was attributed to Ag atoms redistribution as structure defects, increase in the numbers of Cu-Al pairs due to Ag-Al interaction and the Al atoms redistribution around one Cu atom at the sub-lattice of the martensitic crystal.
On ageing, Ag diffusion from bulk to α phase grain boundaries will produce some Agrich precipitates and increase the Al relative fraction available to combine with Cu [4].
So, this stabilization effect may be attributed to Ag atoms redistribution as structure defects, increase in the numbers of Cu-Al pairs due to Ag-Al interaction and the Al atoms redistribution around one Cu atom at the sub-lattice of the martensitic crystal.
This stabilization effect was attributed to Ag atoms redistribution as structure defects, increase in the numbers of Cu-Al pairs due to Ag-Al interaction and the Al atoms redistribution around one Cu atom at the sub-lattice of the martensitic crystal.

With regards to the different extrusion conditions (showed in different colours and numbered from II to VII), the tubes extruded in the condition VII present the highest values of major strain for all tubes lengths.
It was observed that no static recrystallization phenomena take place after deformation, as it is proved by the same irregular grain distribution and grain size in the thickness shown by the bulged tube in comparison with the un-deformed one.
As expected, only in the zone of the large deformations due to the tube bulging, the grains appear stretched and distributed along a preferential direction.

Accuracy of shape dimension is derived from a number of factors such as the rigidity of the machine itself, the interaction between stiffness and machine-tool, the temperature at the incision site (i.e. dilatation effects of heat).
Each technological operation which is performed on the surface of the material causes in the surface and subsurface reconstruction of atoms, molecules and grains of the material.
(operating in the deep layers of the volume of material), II. class: tension acting in grains and crystals in small volumes, III. class: stress acting in the carbon material (dislocations, vacancies, substitutions, etc).
On cooling, the material in the lower part reduces the volume of grains, which are formed on the surface tensile stresses and below the compressive pressure.

Some number of metals have certain properties, which are almost reached its ceiling, and some cannot be made, in principle (e.g., elasticity and high viscosity, the proper heat resistance and heat resistance in an oxidizing atmosphere and under the influence of mechanical loading and temperature above one thousand degrees, etc.).
Accompanying structural phase of self-organization at the grain boundaries polycomposite carried out on a series of scanning device STA.
There are alleged studies «in situ» state of the material as a result of counter-action material alloy components during the changings of external environment in various processes (casting, welding, heat treatment, deformation, machining, spraying), conducting temperature tests the boundaries between grains and phases and the formation of low-energy polycomposite coherent film nanostructures.
During database processing, it is installed a CTA device in internal feedback on the nuclear self-response, controlling the temperature of the coherent alignment of the boundary atoms in the structural formation and cluster units in the grain and interphase boundaries.

A g was precipitated on/from the grain boundaries as well as in the grains.
The grain size of a’ was approx. 5-10 nm.
The subscript numbers i = 1, 2 and 3 refer to elements A, B and C, respectively.

Particle size distribution of cement powder As can be seen in Fig.5, there are many coarse grains (more than 30 µm in diameter) in the blank.
Therefore, it is confirmed that the GAP grinding aid has a good effect on suppressing the agglomeration of the cement powder after grinding and making the grain size distribution uniform.
This can be attributed to the fact that the grain size is reduced to some extent by the grinding aid, and as a result, the cement hydration reaction is promoted.
Therefore, the use of GAP as a grinding aid provides a number of economic benefits. 4.