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Raman spectra analysis allows to make a conclusion about number of graphene layers [8], defects types [1] and concentration [10], and strain value [9].
Hydroxyl and carboxylic groups found in graphene on copper are known to appear at the graphene grain boundaries due to their defective structure [7].
According to existent tendency [8] a ratio of I2D/IG are often used for evaluation of graphene layer number, which is considered to be higher than one if I2D/IG is less than 5.
Apparently, Ar+ bombardment leads to sputtering predominantly the graphene grain boundaries decorated with functional groups and not bound to copper substrate.
Lee, Probing graphene grain boundaries with optical microscopy, Nature Letter 490 (2012) 235-239

INTRODUCTION One of the most important machining procedures is abrasive erosion, defined as a dimensional method consisting in the chip-cutting – scratching – plastic deformation of the part surface by abrasive grains held by a solid, liquid or magnetic support.
This procedure is based on destroying the integrity of the part surface and removing the tooling allowance by means of the dynamic action of erosive agents materialised as solid particles (abrasive grains) [1].
The advantages of water jet cutting over traditional procedures have yielded an increasing number of applications.
The addition of abrasive grains improves the coherence of the jet, amplifies the mechanical effect and increases the cutting speed by about 30%.
An exact analysis of the erosion mechanism generated by the pressure water jet is difficult due to the large number of individual processes which take place at the contact between the incident bundle and the processed part surface.

This material has relatively large sized grains therefore to sample a larger number of grains, at each measurement location, the specimen was rotated by ±2.5°.
Figure 3 – Grain size variation near EB weld Figure 4 - Lattice spacing measured across a toothcomb specimen and corner of EBW3 Comparison between Specimens EBW3 and EBW4.
The grain size of the material is of order 100 µm, due to this it is impractical to choose a smaller sample volume as sufficient grains cannot be measured.
Acknowledgements This research project has been supported by the European Commission under the 7th Framework Programme through “Research Infrastructures” action of the “Capacities” Programme, contract number CP-CSA_INFRA-2011-1.1.17 Number 233883 NMI3 II.

A high number of semi-empirical and empirical approaches, technological investigations and tests, as well as the computer simulation facilitate to find the answer to the complex questions.
When single run welds are used, the typical HAZ of a (Q+T) high strength steels includes: - coarse grained zone, CGHAZ (1100 °C…Tliq), - fine grained zone, FGHAZ (A3…1100 ºC) , - intercritical zone, ICHAZ (A1…A3), - subcritical zone, SCHAZ (500 °C…A1).
The highest peak temperature was selected slightly under than the NST temperature of the investigated steel (1408 ºC), which can result the largest grains expected in real welded joints. 
HAZ Tmax, °C Hardness, HV10 t8.5/5 = 5 s t8.5/5 = 15 s Coarse grained (CGHAZ) 1350 417 385 Fine grained (FGHAZ) 950 418 363 Intercritical (ICHAZ) 800 348 351 With regards to cold cracking, CGHAZ is the most critical, in the welded joint peak hardness values are generally measured in this zone.
After we have had the results of the further tests, we may decide whether it is necessary to increase the number of specimens when performing tests with one parameter respectively (third direction)

A number of experiments were conducted and the results are presented and discussed in this paper.
To obtain fully dense alumina for translucency, the residual porosity inside the grains and along the grain boundary must be removed.
One could argue that the hydrogen diffuses very fast in the hexagonal alumina crystal lattice and drags the trapped pores inside the grain to the grain boundaries.
Bimodal grain structure and practically free from porosity with grain size ranging from about 10 to 70 micron.
Large grains fracture transgranularly.

These materials will continue to remain a focus for studies, and researchers will broaden both the number and type of cations incorporated and also introduce other non-metals (e.g. [6]).
Increasing numbers of researchers are reporting the production of transparent oxynitrides; this has particularly been the case with α-sialons [7,8], where not only a fine starting grain size but also the achievement of clean grain boundaries (see Figure 3) is important in achieving good transparency.
(a) Transparent Lu α-sialon ceramic and (b) its clean grain boundaries (after [8]).
An α-sialon ceramic heated by numbers indicate the LiAl5O8/AlN content SPS at 200 o Cmin -1(left) and the same in the starting mix (after [10]).
A surprising feature of research in the last few years has been the relatively small numbers of papers on oxynitrides focusing on the nano field.

Until now, the investigated alloys are ongoing research to resolve, the investigation was carried out to employ rapid quenching by melt spinning to produce Mn–Ni–In Heusler alloys by JLSánchez Llamazares et al [8], and the ribbons of Ni-Mn-In Heusler alloys grain preferential texture.
According to the Hume-Rothery theory [9], electron concentration is from 7.88 to 8.02 because of the valence electron number of Gd , and the crystal structure stability is decreased so that the martensite transformation temperature rised.
Fig.4 The microstructure of Ni50Mn34.5In13.5Gd2 alloys (100×) Fig.3 The microstructure of NiMnInGd alloys (1000×) Ni50Mn34.5In15Gd0.5 (a) Ni50Mn34.5In14.5Gd1 (b) It can be observed From Fig. 4, that a new phase is separated out in the grain boundary with the increase of Gd.
When the Gd addition is up to 1,2 at.%, precipitates of the grain boundary are increased.
And it is found that the grain boundary second phase increased significantly , due to the increase of Gd content.

It was found that the grain size of the films decreases and the surface becomes smoother and more uniform by increasing the pH solution.
The morphology and size of the CuO nanostructures has been controlled by a number of different techniques.
It can be concluded that the increasing of pH solution will affects the grain size and homogeneity of the films.
Furthermore, the grain size decreases slightly when the pH solution was increased.
Besides, the grain size of the films also decreases with an increasing in pH solution.

However, the compressive strength and compressive strain of porous TiNiMo alloys with excessive Mo content decrease sharply and the failure manner turned into brittle fracture mode, which results from a large amount of Ti2Ni and Ti4Ni2O phases precipitated at grain boundary.
It can be seen that crystalline grains of porous TiNi alloy without doping Mo are fine and many thin lath martensite variants (B19') exist at the intragranular (Fig.1a).
A large number of big and small dimples and several tear ridges are observed.
As a result, a large amount of Ti2Ni and Ti4Ni2O phases precipitate on the grain boundary with an increasing of Mo content.
The compressive strength and compressive strain of porous TiNiMo alloy with excessive Mo decrease sharply and the failure manner turned from ductile mode into brittle fracture mode, which results from a large amount of Ti2Ni and Ti4Ni2O phases precipitated on the grain boundary.

H-K plot actually suggested that the number of thses holes decreased with increasing aging period.
Three possible mechanisms of the shape instability have been proposed: (a)fault migration model [4, 5, 8], (b) capilarity-induced perturbation model [9] and (c)grain boundary thermal groove model [10, 11].
The thermal groove model is generally accepted as the main mechanism for the spheroidization of deformed pearlite, since many sub grooves are present on grain boundaries.
The Euler number() is three-dimensional one in this study.