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Take the average weight numbers for room temperature tensile strength, high temperature tensile strength and Brinell hardness as 40, 50 and 10 respectively.
Since the piston is mainly used under high temperature, its weighted number of high temperature tensile strength is greater than the room-temperature one.
This phase is usually located at grain boundaries of α (Al), the size of which is generally relatively large and angular.
As a result, excessive Ce in the melt will concentrate to grain boundaries where atoms are irregular arranged and will adsorb on the surroundings of Fe-rich phase that grow at the grain boundaries as well, hindering the diffusion of Fe.
When the content of Ni is relatively low, Ce can replace the position of the Ni in the alloy, forming into a certain number of Al-Ni-Cu-Ce phases.

Journal Title and Volume Number (to be inserted by the publisher) 3 Saturation magnetostriction constant, λs, depends on annealing temperature similarly to coercive field.
In all the cases the average grain size of bcc-(Fe,Co,Si) crystals was similar, and varied from 8 to 10 nm.
No clear dependence of average grain diameter on Co content was found, hence it can be concluded that the coercive field does not strongly depend on the grain size of nanocrystalline Co-Finemets.
The amount of RM, 7 or 9 at. %, is less important in Journal Title and Volume Number (to be inserted by the publisher) 5 this case.
Journal Title and Volume Number (to be inserted by the publisher) 7 [8] T.

A powder grain size between 10 and 37 μm is used for thermal spraying.
The substrate surface was corundum-blasted before spraying with a grain size between 60 and 120 μm.
The grain size of the spraying powder is between 10 and 40 μm.
Oxidation at the grain boundaries can already be noticed in optical analysis (compare e.g. figure 2(a)).
Energy dispersive X-ray spectroscopy (EDS) confirms that chromium oxide is forming on the grain boundaries.

Figure 3c shows surface area of carbon materials in the district 4 further smooth, particle surface began to form more tiny filamentous microcrystalline; Figure 3d displays 3 large particles began to stretch flat smooth surface area of carbon materials, the decrease in the number of microcrystalline particles, grew up, began to development form irregular graphite crystals; Figure 3e shows graphitized microcrystal of carbon materials in the district 2 further grew up, part of the grain formed a thick piece of layer structure of hexagonal grain; Figure 3f shows s graphitized microcrystal in the district 1 further develop, grain thickness thinner obviously, form the ideal flat graphite crystals.
When temperature is close to 2600 ℃, the original grain clearly take on the piece of layer structure of the edge. when the temperature is above 2600 ℃, grains will generate complete structure, good performance of graphite crystals.
Then the defect of graphite crystal structure itself is ignored, if carbon material graphitized from anthracite under ultra high graphitization temperature compared with pure graphite , clearly known that: D peak of carbon materials in district 3 red shift 7 cm - 1 ,G peak red shift 5 cm - 1 compare with pure graphite; D peak of carbon materials in district1 red shift4 cm - 1 ,G peak red shift 5 cm - 1 compare with pure graphite.And carbon materials of district 3 and district 1 have ID/IG < 1, show carbon atoms of carbon materials that prepared by anthracite under ultra high graphitization temperature have been excellent neat, the number of sp3 hybridization of atoms less than the number of carbon atoms of sp2 hybridization in the graphitized carbon material microstructure.

The SEM of fracture surfaces showed that the number of dimples increased with the increase of aging temperature.
Compared with cold rolling Cu-2.7Be alloys (Fig. 2(a)), precipitates are found in the grains and along the grain boundary (pointed out by red arrows in Fig. 3(b),(c),(d) ).
However, the number and distribution of precipitates are different depend on the aging process of samples.
Due to the pre-heating treatment at 180 oC/2h, samples of two-step aging (Fig. 2(b)) own more number of precipitates than samples of one-step aging (320 oC/2h).
When aged in lower temperature, high density of G.P. zones can be obtained and the G.P. zones can be the core of the followed precipitated phases, which could increase the number of strengthening phases ( Fig. 3(c)) and could be the reason for the strength increase of two-step aging in the curves of 340 oC/4h and 380 oC/4h.

The results obtained by means of comparing the bright and dark field indicate that the average grain size of the surface is 13.94nm.
From the morphology of surface undergoing strengthened shot peening,it is not difficult to find that there are a great number of traces due to repeating bombardment of bullets.
It can be explained that the refinement of the grains after nanocrystallization and work hardening after strong plastic deformation both lead to the improvement of the hardness[6].
Some contacts appearing delamination are owing to the reason that the increasing temperature lead the transformation of the organization and structure and once the temperature is suit for nano-grains’ growth,the surface would fail to lose protection[7].
The reason for this is that nanocrystallization may lead the increase of the amount of grain boundary whose volume ratio increase a lot with grain refining.

The ‘B’ increases the bainitic hardenability of steel by retarding the heterogeneous nucleation of ferrite at the austenite grain surface [2].
It is probable that this effect is due to the reduction in interfacial energy as the ‘B’ segregates to the grain boundaries.
This in turn makes grain boundary less effective as heterogeneous nucleation sites.
The ‘Ni’ additions lead to grain refinement within the microstructure.
Material and Experimental Method To development of welding wire for submerged arc welding of X-120M steel line pipe by using transmission electron microscopy, number of test coupons have been made from V-Nb-Ti-B micro alloyed steel with low Pcm steel plate of API-5L, X-120M.

However, the broadenings of diffraction peak indicate grain refinement.
According to Scherrer equation, the average grain sizes of pure TiO2 particle and the Ni2+ doped TiO2 particle are 18~26nm and 13~17nm, respectively.
The photo indicates that there are a large number of larger uniformly distributed spherical particles on the film surface.
Combining Fig. 1 and 2, the TiO2 thin films doped with a small amount of Ni2+ have smooth surface, and expansion of crystal lattice of TiO2 suppresses the growth of crystal grain of TiO2, resulting in TiO2 film surface grain size diminishing but the proportion of surface atoms and surface area increasing.
However, it could inhibit the grain growth and make the lattice distort.

The structure is sufficiently dense, with a grain size of 100-200 nm (Fig. 1a).
Fig. 2 shows the quantitative distribution of the grains’ size and their percentage in TiNiTa coating.
Table 1 Chemical composition of mechanically activated powder cBN20Co10NiAl65Y5, wt. % Brand B N Fe C Ca Co Ni Al Y cBN20Co10NiAl65Y5 10,82 9,53 0,62 3,57 0,12 8,63 29,91 31,68 5,12 The structure of cBN20Co10NiAl65Y5 layer is sufficiently dense, with a grain size of 150-300nm (Fig. 6a-c).
We determined the optimal processing parameters to ensure the formation of a surface layer with a grain size of 100-350 nm with a Micro Hμ = 18,3 ÷ 18,5 GPa.
Acknowledgements The work was performed as part of the government task № 9.555.2014/K with the financial support of the Ministry of Education and Science of the Russian Federation and the President grant number MK-5445.2016.8.

d l Fig.4 A typical Vickers indent at 10 kg load Fracture of AlMgB14 analysis.The fracture image of AlMgB14 is shown inFig.5, a river fracture pattern, consisting of a large number of small steps and potholes, cleavage cracks through grain boundaries and stretches to adjacent grain.
From arrow 1 in Fig.5 are shown new cleavage cracks emerged in grain boundaries or internal adjacent grain, with the means to external expansion, throughout the grain.
From arrow 2 in Fig.5 are shown crack produced in grain boundaries.The obvious features of brittle fracture is the common features of ceramic materials.