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As prerequisite for quality jobs in steels, normalizing is an important heat treatment process to obtain critical room temperature grain size before undergoing subsequent heat treatments [3].
Normalizing treatment breaks up continuous pattern coarser phase along the grain boundary [10].
The Vicker’s hardness number is used for hardness analysis.
This is attributed due to the refinement of grains in normalizing (air cooling) [13].

Four different readings were taken around the welded circular area; the same number of readings was then taken at an interval of 5mm away from the welded area longitudinally.
The torsion test demonstrates that the un-welded specimens were broken in the middle whereas, the welded ones was broken at the HAZ due to overheating of this area, so grain growth was promoted by the absorbed heat [12], consequently, coarse grains was developed in the HAZ, these coarse grains caused a decrease in the mechanical properties of the welded specimen as proved by the torsion and corrosion [7].

On the other hand, fine particles give rise to a homogeneous (though high density) distribution of dislocations during deformation, which reduces the possible number of recrystallization nucleation sites during annealing.
In addition owing to the pinning effect of particles on the movement (migration) of boundaries, closely interparticle spacing makes it difficult for local lattice curvature regions to transform into recrystallization nuclei, which can then grow into fully recrystallized grains.
The dispersed nano-alumina particles can serve as the sources of dislocations and exert pinning effect on dislocations and grain boundaries during deformation (Fig.2) and annealing treatment.
Vol.233~237(1996), p.127 [6] A.Upadhyaya and G.S.Upadhyaya: Materials and Design Vol.16 (1995), p.41 [7] S.F.Moustafa, Z.Abdel-Hamid and A.M.Abd-Elhay: Materials Letters Vol.53 (2002), p.244 [8] P.Cotterill and P.R.Mould: Recrystallization and Grain growth in Metals, Surrey University Press, London, 1976 [9] S.H.Kim and D.N.Lee: Mater.

On remark the presence of homogeneous martensitic structure and fines grains of δ ferrite and small black inclusions of Si oxides.
The martensitic structure is homogeneous with fines grains of δ ferrite and small black inclusions of Si oxides.
In figures 9,10 are presented the electron microscopy on the sample Cu-Zn alloy and remark the structure α + β with fines grains being coating by a thin layer of Ni of microns order.
Acknowledgment This work is supported by the Sectorial Operational Programme Human Resources Development (SOP HRD), financed from the European Social Fund and the Romanian Government, under the contract number POSDRU/159/1.5/S/138963 – PERFORM.

However, limited by the growth method, CVD diamond still remains polycrystalline in its nature, resulting in a number of grain boundary densities.
One the other hand, our diamond are polycrystalline, grain boundaries present in the diamond.
While the impurities and grain boundary defects can act as trapping and recombination centers of carriers.

With increasing Ba 2+ content, the peak positions firstly shifted to lower 2θ angle indicating a increasing in the lattice parameter of the solid solution because of the relatively larger ionic radius of Ba 2+ (0.161 nm, coordination number CN=12) than the ionic radius of Ca 2+ (0.134nm,CN=12) entered the A-site of the ABO3 perovskite structure [3].
As Ba 2+ content increased from 1.5mol% to 5mol%, grain size increased.
Generally, the Qf value are mainly influenced by the porosity, grain size, impurity and secondary phase and so on [5].
It has been reported that grain size does not significantly affect the Qf value [6, 7].

Many different-sized grains were observed on the surface of the flats in SEM photographs, in which the Ca/P ratio of the particles (marked in fig 2a) was 1.67, demonstrating the presence of HA particles.
The top layer has a large number of tiny pores with the different pore size, prepared from single HA powders.
Therefore, it is reasonable to sur- mise that the fine nano-sized grains in the FGC were formed from the metastable amorphous phase.
(a) surface of the coatings and (b) cross-section of the coatings Fig.3 TEM micrograph showing (a) nucleation site of hydroxyapatite grains and (b) t- ZrO2 phases.

Water impurities are commonly suspended particular which contain organic and mineral composites with grain size between 7.1 and 12.7 µm [11].
It correspond with decreasing number pores which form and surface area porous composite.
Adjusting time of heating process increases sufficient thermal energy to melt the grains of waste glass.
The melt of grains waste glass lead to decreased pore size and surface area cause form glass back as illustrated in Figure 5.

In the modeling only for tangential and radial directions were considered, but the movement of moisture along the grain was the highest, and it influenced on the moisture distribution, especially in the end of work part.
Therefore, it is necessary to develop the model, including the internal pressure and movement of moisture along the grain.
Drying time is determined by multiplication of the cycle number and the cycle time together.
Timber anisotropy is considered by different coefficients of heat and moisture transfer throughout the grain.

The ore is mainly crystalline structure, followed by the account of the structure of the solid solution separated structure, locally have recrystallized structure, pressure, and grain internal structure.
Chalcopyrite and gangue close relationship based, fine-grained disseminated coarse, medium, fine, micro- disseminated very uneven.
The ore belongs to the fine grained embedded cloth polymetallic ore. 1.1 Ore chemical analysis of the multi-element In order to understand the nature of the ore, analyzed the chemical element.
Closed-circuit test In the best agent conditions, we were scavenging and selection of the number of times, The test results show that one stage of scavenging and two stages of cleaning flotation is necessary, In order to verify the stability of the test, one stage of roughing, one stage of scavenging and two stages of cleaning flotation, middling’s order to return to the closed-circuit test research, testing process, the results are shown in Figure 5 and Table 3.