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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.

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.

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).

In addition to layers high adhesion strength, a number of requirements are imposed on bimetallic brass-steel-brass strips in terms of dimensional accuracy, mechanical properties and microstructure [6].
Relative reduction during cladding affects bimetal layers adhesion strength, character of microstructure, the size of recrystallized grains, strip mechanical properties, and dimensional accuracy [7].
Large values ​​of joint deformation degree lead to excessive grain refinement after recrystallization process and increase material mechanical properties anisotropy, while lower values ​​contribute to excessive growth of ferrite grains during annealing and surface deterioration after stamping [8].

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).

The interest in packing structures dates back to early times when the grain packings called “heaps” were the first things that were ever measured in ancient civilizations both for trading or taxes collection [1].
For convenience, Eq. (3) is often rearranged in a friction factor-Reynolds number dimensionless correlation.
The penetration efficiency per number of solid spheres is documented in Table 3.
The penetration efficiency per number of solid spheres is also depicted in Fig. 3 in terms of Stokes number expressed by (8) where St is the Stokes number and cc is the Cunningham slip correction factor [7].
According to Fig. 3 we come to the conclusion that the influence of the Stokes number in PN is negligible for 10-5≤St<10-3.

Both alloys are in the form of 50 µm thick foils and have similar phase composition and similar average grain size.
In the case of 0C404, there is in addition a large number of smaller particles (a few hundred nanometers in size).
Both alloys form transition-metal oxide particles at the gas/scale interface, the number and size of the particles increasing between 150 and 500 hours.
They argued that it is due to the fast diffusion of Mg through the oxide grain boundary [3].
Especially, investigations involving simpler alloy systems (with a smaller number of alloying elements) would be helpful.