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The NA has an almost round grain shape (small to mid-portion of irregular, sharp or elongated grains) and it is supposed to perform well in pervious concrete.
Its surface is smooth, unlike ACBFS, which is of irregular grains shape and sharp edges.
Maximum size of aggregate grain in the experiment was chosen as 8 mm.
As for NA (round, smooth and no porous), the binder material only covers the grains, forming layer of a certain thickness, thus the effect of filling the gaps between the grains is stronger.
Acknowledgements This research has been carried out within the project supported by Slovak Scientific Grant Agency VEGA (grant number 1/0524/18).

Each layer consists of columnar grains.
The side layers consist of nearly equiaxed grains.
In the surface layer, grain boundaries appear bright, and their thickness increases in the order S1, S2, and S3.
The Si content might affect the number of layers.
The shape of a-Al grains is not drastically changed at the roll bite.

In addition, in the process of ultrasonic treatment, a large number of cavitation bubbles will be generated in the metal melt.
In addition, the process can also affect the size and morphology of α-Mg grains.
Under gravity casting, α-Mg grains were coarse dendrites with a larger size of 101.2 μm.
After UT, the α-Mg grains became more round and the grain size decreased greatly, about 55.6 μm.
In squeeze casting after UT (Fig. 6d), α-Mg grains change from coarse dendrites to round petal-shaped grains, and the grain size is the smallest, about 49 μm.

However, copper-based SMAs such as the ternary Cu-Al-Ni are not easily deformed in the lower temperature martensitic phase which can be attributed to brittleness induced by coarse grain size, high degree of order and elastic anisotropy.
It is due to the coarse grain sizes, intergranular cracking and high elastic anisotropies.
There are several methods to improve the ductility of the polycrystalline copper based shape memory alloys such as grain refinement [8, 9], addition of alloying elements [10], formation of single crystals [11] and thermomechanical treatments [12].
Furthermore, the types of material, grain size, martensite interface density, and defect structure, are important internal variables [6].
Acknowledgement The authors gratefully acknowledge the financial support for this research provided by Universiti Teknologi Malaysia and Ministry of Education under the Fundamental Research Grant Scheme (FRGS) vote number 4F945.

Optical microscopy, scanning electronic microscopy (SEM), fourier transfer infrared spectroscopy (FT-IR), and thermal gravity analysis (TGA) were used to determine the properties of prepared microcapsules such as grain size and their distribution, wall thickness, content of core materials and thermal performances of microcapsules.
Results showed that the average grain size was 210 μm and the wall thickness was in the range of 1.8-5 μm depending on agitation rate.
Moreover, the small content of -OH indicated there have large numbers of cross UF.

It is supposed that the number of valence electrons per atom for Ni, Mn, Fe, Ga atoms as 10(3d8, 4s2), 7(3d5, 4s2), 8(3d6, 4s2), 3(4s2, 4p1), respectively.
Jin et al. [10] found that the relationship between martensitic transformation temperature and the average number of valence electrons per atom is as follows: Tm=702.5(e/a)-5067 K, which predicted that the Ms increases with increasing e/a value.
In general, a large proportion of martensite variants are reoriented toward one and the same direction in the single crystal, while the grain boundaries obstruct the reorientation in the polycrystal.
The improved MFIS in the annealed sample can be attributed to the number of the grain boundaries.
This may be the Fe atoms enhance the grain boundaries of Ni54Mn20Fe1Ga25 alloy leading to the increase of plasticity.

The dispersant will increase a large number of net charge on the surface of β-SiC particle in water.
As we can see from the Fig.5 (a), there are a large number of flake grains and they stick together.
What’s more, the basic grain size is about 1μm.
A large number of fine particles still exist in Fig.5 (b), the particle size is less than 1μm.
However, there are still flake grains and agglomeration which formed by fine particles adsorbed in the surface of the larger particles.

Table 1 Main parameters of cement Density （kg/m3） Cement fineness Compressive strength（Mpa） Flexural strength （Mpa） Setting time（min） Stability 3d 28d 3d 28d Initial setting Final setting 3070 2.34% 7.8 11.2 35.3 49.7 217 263 qualified (2) Fine aggregate Common sand which bulk density is 1678kg/m3, maximum grain size is 5mm and fineness modulus is 2.73
(3) Rubber powder The rubber powder is maximum grain size is 2mm
Table 2 Main parameters of haydite Bulk density（kg/m3） Apparent density（kg/m3） Porosity（%） Cylindrical compress strength（Mpa） 1h Water absorption（%） Grain composition Particle size coefficient 800 1470 45.6 8.5 8.8 5-16 continuous size fraction 1.1 (5) GRT fiber The main parameters is shown in Table 3.
Acknowledgements This work was financially supported by the Provincial Speccial Major Project of Forest Engineering (project number:501035),the Experimental Teaching Center of Provinical Structural Engineering (project number:501042),and the key Discipline Project of Forest Engineering in SWFU (project number:47002801) References [1] Eldin N N, Senouci A B.

A number of studies have examined the in vitro corrosion behavior of magnesium alloys and devices [2].
The corrosion behavior of AZ31 magnesium alloy with different grain sizes immersed in simulated body fluids was compared in chloride solution and in phosphate-buffer solution (PBS) [7].
In this study, the condition of the fluid flow rate 250ml/min and 500 ml/min were laminar fluid flow because each Reynolds number was calculated 666 and 1332.
Escudero, Corrosion behaviour of AZ31 magnesium alloy with different grain sizes in simulated biological fluids, Acta Biomaterialia, vol. 6, no. 5, pp. 1763–1771, 2009
Moitra, Grain size effect on microstructural properties of 3D nanocrystalline magnesium under tensile deformation, Computational Materials Science, vol. 79, pp. 247–51, Nov. 2013.

The structure of Zr700 sheet in as-is state, i.e. before bonding is characterized by the structure of α phase grains.
The carbon steel (P355NL) microstructure in as-is state characterized by an equiaxed structure of middle-sized grains pearlite and ferrite.
For pearlite, we can see a band structure of fine grains, typical for materials that underwent hot forming.
The measurements were performed with an accuracy up to 0.01 mm with numbers of loading cycles N recorded.
Figure 4a shows the crack lengths (specimens sp.3.0 and sp.2.8) depending on a number of cycles of loading changes obtained during oscillatory bending.