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As examples, the measurable diffusion of solute occurs in the solid phase during and after solidification, diffusion in the liquid phase may be hindered at high cooling rates, the dendritic grains evolve during solidification with dissolution of some finer arms, etc. [3].
Diffusion at high temperatures and the existence of both sub-grain and a high number density of dislocations in the aluminum cast [4], which contributes to the pipe diffusion, will help to homogenize the chemical gradient within the dendrite phase created during its formation and approaches the average composition of the pre-eutectic dendrite phase.
In the above approach to calculate room temperature yield strength, for the sake of simplicity, grain size contribution of the cast (Hall Petch Effect), primary intermetalic phases and casting defects have not been taken into account.

In order to avoid any particle segregation due to gravity and grain size effects, the basic and additive element powders were mixed manually in a small glass container for 30 min.
Capillary force attracts the W-W grains together and help slide and rearrange the W particles to be more closely compacted.
Acknowledgements The authors would like to thank the Universiti Sains Malaysia (Incentive Research grant number (1001/227/PBAHAN/8044001) and the University of Omar Al-Mukhtar Libya for their motivation and encouragement in carrying out this work.
Fang, Microstructure and properties of fine grained W–15wt.% Cu composite sintered by microwave from the sol–gel prepared powders, J.

Introduction Metal bond grinding wheels are mostly used for super-abrasive grains because of their improved bonding strength [1].
Different dressing methods have been proposed aiming to improve the dress-ability of this kind of wheels, which is of great important process to provide sufficient chip space and grain protrusion.
In addition, It will cause pollution of the working environment and mechanical damage of the abrasive grains between the wheel and the truer/dresser[3-5].
Quite a number of micro-cracks distributed on the surface of the tin bronze based bond diamond wheel with high porosity (38%) after it ground for a period of time at a higher rotating speed and bigger depth of cut [9].

Among these cathode materials, LiNiPO4 which exhibits high potential (5.1 V) [2] for battery applications has gained attention from a growing number of researchers, despite the lack of a stable electrolyte for this high operating voltage.
The results demonstrated well developed grains of different shape which are closely connected to each other.
It can be obviously seen that the particle/grain size of the doped sample is very much larger than the undoped sample.
The increase of grain size is in agreement with the calculated crystallite size and lattice parameters.

Soon after, it was sieved by using the Bertel sieve, 0,589 opening, number 28 from the Tyler standard series.
The rounded-shaped larger grains were described as foundry sand mixed with other dust types.
The diameter of such grains measures from 4.8 mm to 0.075 mm [3].
Additionally, morphologically compact particles were also noticed, probably related to quartz grains present in the analyzed sample of waste.

The same phase was also identified in the case of using NaCl (Fig. 1c) and KCl (Fig. 1d), however, compared to using LiCl, the peak of MA spinel was lower and the peak of Al2O3 and MgO were higher, revealing that large number of MgO and Al2O3 did not react completely.
When magnified again, each MA spinel crystal grains were round plate with different shapes and sizes, the crystal grain sizes were between 3 and 8 μm.
Further observed from the surface of products, there were small grains with octahedral structure.

Modern self-compacting plasticized concretes contain a water-dispersion-fine-grained matrix (water, cement, ground stone flour, silica fume, fine sand fr. 0,16-0,63 mm).
It should be noted that non-conforming raw materials with a grain size of less than 5 mm, formed in an amount of 10-15% or more of the production volumes in the production of broken natural stone in quarries by crushing stone rocks, can be successfully used as aggregates and dispersed fillers for the production of all types of modern concrete.
Reotechnological indicators of the suspension of the reaction-powder concrete mixtures Composition number Type of stone flour SF, [sm] W/H RDS 0 (control) Dusty Quartz 30 0,125 8,0 51,1 1 (control) Dusty Quartz 30 0,123 8,0 62,3 2 Dolomitic limestone 30 0,117 8,0 61,7 3 Dolomite 34 0,117 10,6 61,8 4 Glauconitic sandstone (porous) 30 0,154 8,0 62,3 5 High calcium limestone (calcite) 32 0,123 9,2 62,1 6 Quartz sandstone (dense) 30 0,123 8,0 62,0 7 Diabase 31 0,123 8,6 61,6 8 Granite 32 0,115 9,2 61,4 A concrete mixture on powdered quartz and silica fume was prepared as a control (composition 1, Table 1).
This can be explained by the fact that sandstones by origin consist of cemented sand grains and in a highly dispersed state also have a negatively charged surface.

Optimization of conditions at all stages of surface modification ensured the formation of the structure of the surface layers of fine-grained nanoscale of 20–190 nm (Fig. 1).
The figure shows the grain size distribution and their percentage in the coating TiNiCu (Fig. 1, c) and TiNi (Fig. 1, e), the results of data processing in the program Statistica 6.0, derived from VideoTesT-Structure 4.0.
The microstructure of the surface layers of: a) TiNiCu×10000; b) - TiNiCu ×20000; d) TiNi ×50000; e) - TiNi ×150000; average grain size and percentage - c), f) Microhardness measurements were carried out on a PMT-3, and the structure and phase composition of the surface layer were examined by X-ray diffraction and optical microscopy.
A number of studies [3,4] show that for alloys with SME (TiNi) the superelastic properties of deformation zones have a direct impact on the wear mechanism of the alloy.

It is possible to observe lamellae of transformed alpha (lamellae generated from beta grains) and equiaxial primary alpha grains.
Furthermore in figure 3a it is also possible to note that the grains are elongated along the stretching direction.
An approach with tetrahedral element was selected to mesh the workpiece and, because of the slender geometry of the workpiece, a high discretization level was imposed (number of element 135000 about).

The assumed mechanical properties are summarized in Table 1, where g is a mean value of wood density, E0 and E90 are the longitudinal and transversal moduli of elasticity, n0 and n90 are, respectively, the Poisson’s ratio in longitudinal and transverse direction according to technical literature [6], G0,90 and G90 are the shear moduli in the parallel-perpendicular to grain planes and in transverse planes, respectively.
Stress condition Characteristic strength [N/mm2] Design strength [N/mm2] kmod = 0.50 kmod = 0.65 Compression // to grain (fc,0,k) 22 (c) 22 (p) (fc,0,d) 8.5 (c) 8.5 (p) 11 (c) 11 (p) Tension // to grain (ft,0,k) 17 (c) 16 (p) (ft,0,d) 6.5 (c) 6.2 (p) 8.5 (c) 8.0 (p) Bending (fm,k) 28 (c) 26 (p) (fm,d) 10.8 (c) 10.0 (p) 14 (c) 13 (p) Shear (fv,k) 2.0 (c) 2.7 (p) (fv,d) 0.8 (c) 1.0 (p) 1.0 (c) 1.4 (p) In Figure 8 the deformation and stress state of three representative structures at present time, which is the worse condition, are plotted.
Due to the variability of cross sections beams, in order to avoid a number of different collars geometries, the system was conceived in only three types (single, double or triple sections) allowing the adaptation of the system to the irregular surface of the existing ancient beams by the interposition of a layer of rubber, which is vulcanized to the steel collar in the workshop (Fig. 9).