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Optical micrograph shows that increasing of bioglass content lead to smaller grain size.
Numbers of accident rates involving bone fracture are increasing every year.
With the addition of bioglass into magnesium matrix, the grain size becomes smaller.
Bioglass acts as a hindrance for magnesium grain growth.
Microstuctural analysis showed that Bioglassis segregated alongside grain boundaries and the existence of pores can be observed isolated at the grain boundaries and around the bioglass particles.

The mean surface roughness and the grain size increase with increasing thickness of deposits on the same substrate. 1.
The presence of large grains on the surface of the W-Ti deposits confirms the formation of 3D islands, which compose high number of small grains.
The characteristic of this mechanism is a high energy of interaction between the atoms of deposits, therefore atoms adsorbed on the surface have high mobility and small grains are associated by the surface diffusion to form large 3D grains.
The grain size increasing with increase of thickness of W-Ti deposits, as can be seen in Fig. 4 (a-b).
The grain size and surface roughness of deposits increase with the increase of deposit thickness.

When material is yielded, its internal grains slip along the slip plane under shear stress.
With the increase of stress, the plastic deformation grains are more and more, large numbers of low amplitude continuous acoustic emission signals appear.
Continue to increase stress in the process of material aggrandizement, with grain dislocation density increasing, a large number of dislocation intersections appear.
Conclusions (1) Temperature can affect free dislocation motion's P - N force in grain.
(3) When the temperature is lower than embrittlement temperature, material is embrittled, judging from the microscopic mechanism, brittleness relates to the resistance in the movement of dislocation in the grain lattice, when resistance increases, the material yield strength will increase, although plastic deformation develops slowly there will be some brittle fractures, thus great energy signals appear, count increases.

There are a number of observations [15-17] demonstrating that corrosion susceptibility have been related to the precipitation of the Mg-rich -phase (Al3Mg2) at grain boundaries of Al-Mg alloys.
Thus, using Student’s t-criterion for the confidence level and the number of degrees of freedom, Student’s coefficient is [20].
A fractograph obtained with higher magnification (see in the insert in Fig. 2 d) shows a number of the precipitation phase, (CuAl2 and/or Al2CuMg), visible on the brittle surface of D1 alloy charged with hydrogen for 120 h (3).
One can assume that presence of hydrogen the second phase precipitation phase at the grain boundaries may decrease the grain boundary cohesion resulting in intergranular fracture of the D1 alloy.
The corrosion properties of semi-products manufactured from the Al-Cu-Mg alloy system are determined by the composition and distribution of precipitates at the grain boundaries and within the grain bulk and by the extent of copper depletion from the near-boundary regions, which in turn depends on thermal treatment conditions.

The grain size, deposition rate as well as thickness of the obtained films rose up with increasing sputtering power.
As is seen, the grain size of films increased with increasing sputtering power during deposition (see Table 1).
Thus, the number of Sn and O atoms arriving at the substrate increased gradually with increasing sputtering power, which would increase the probability of inter-atomic collisions, finally leading to increasing grain size in the films.
In particular, the annealed sample exhibited highest electrical resistivity (about 4.17×107Ω·cm) than all the as-deposited films samples owing to the least number of VO in such film.
The grain size, thickness and depositing rate of the obtained tin oxide films all increased with the increase of sputtering power.

They are analyzed in detail and discussed based on their formation mechanisms, which are growth selection during solidification and the formation of new grains during casting and recrystallization, glide on selected slip planes during plastic deformation and oriented nucleation and oriented growth of new grains during recrystallization.
In certain alloys also a local twin orientations may form due to specific low boundary energy configuration along the directionally solidified grains.
The grain interaction as postulated in a strict form in the Taylor model has been modified in the “GIA” (grain interaction) deformation texture simulation models, reaching a high level of accuracy /9,21/.
Hence, nuclei emerging from the cube-bands (i.e. cube- and cubeND oriented grains) and the grain boundaries (i.e.
R oriented grains) will prevail in the corresponding recrystallization texture /12/.

Both types of grains, ferritic grains and pearlitic nodules, were included in grain size measurement.
Grain size was approximately 10 µm, it ranged from 7.8 µm to 11.3 µm.
The number of these particles always decreased with increasing heat treatment temperature.
Microalloying with vanadium resulted in grain refinement probably thanks carbonitride and sulphide clustes that effected as nucleation centres for ferrite grains.
Acknowledgement This work was supported by a Grant number 106/03/0473 from the Grant Agency of the Czech Republic.

Micro structural investigation of cracked specimens: To analyse the cracks, micrographs (250 X scale) of typical ATIG welded cracked specimen are compared with FBTIG specimens of experiment number 4 in Fig 2.
FBTIG specimen has finer grain structure compared to ATIG specimen.
The cracks are liquation cracks along the grain boundaries which is confirmed by thickened grain boundaries observed in SEM micrographs.
Excessive grain boundary liquation is the cause for the cracks in ATIG welding.
Because of the absence of continuous thickened grain boundary liquation and due to the presence of finer grains, FBTIG welds do not exhibit cracking tendency.

Reynolds number of sand movement: Where, —the air kinematic viscosity.
two-phase particle velocity distribution equation Space to any grains of sand, may be the point of origin of the displacement of a "bit vector" r to determine the resulting vector can also be rectangular coordinates x, y, z to determine.
If a particle at time t and time t+dt is not within the phase-breaking collision with other grains, its speed from u into u+Fdt, and it becomes a function of position by the r to r + u dt.
(15) If there are vector notation[6]: f is the particle velocity distribution function, which can be expressed as: f=f(u, r, t) is the physical meaning of coordinates in space r and time t, u+du sand at speeds of between the number of grains of sand, where du=dudvdw, u is the random particle velocity, F is the role of force in the sand on a few: units of gravity; the face of resistance (parallel to the direction of sand movement, in the opposite direction); buoyancy, parallel to gravity, in the opposite direction; break collision impact.
Once it has been determined, the macroscopic properties of a series of sand movement can be obtained, such as sand average speed, and number per unit volume of sand.

The rapid solidification yields fine grained microstructure such that the enhancement in mechanical properties can be obtained [8,9].
Experimental The die set was made up of H11 die steel since the die steel has got the ability to withstand high temperatures and high pressures for maximum number of production settings.
The experimental conditions and the values of number of cycles to failure obtained from the squeeze cast components were given in the Table 2.
The tensile strength of the components were found to be 165 MPa, 196 MPa and 220MPa respectively and the number of cycles to failure were found to be 65698, 78942 and 84291 respectively.
From the results, it is evident that when the level of pressure applied is kept at the highest level, the squeeze cast components exhibited improved mechanical properties owing to the attainment of fine grained structure.