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The high pure and finer grain steel can be obtained by deep deoxidation technology, deep desulfurization technology, low nitrogen and microalloy-technology of Boron/Niobium/Titanium.
The grains are uniform and fine.
The grain size of SPHC, QSTE340TM and QSTE460TM is up to 7.5, 11.5 and 12 grade, respectively.
The numbers of test sample are from 44 to 300.
Near the weld seam, there was the normalization fine grain zone, which hardness value is lower than that of weld seam structure and is higher than that of matrix structure.

Moreover, an improved pulse RTA method combining low temperature (550 oC) for activation and high temperature (850 oC) for rapid nucleation and grain growth was put forward by Y.
Compared to the Si film annealed at lower temperature of 750 oC, the Si film annealed at higher temperature of 1100 oC possessed more condensed and larger grain size and, moreover, it had more nuclei in film.
The larger grain size and greater surface roughness is supposed to be attributed to more energies supplies for the Si atoms, arising from higher RTA temperature, leading to the notable transfer of Si atoms to the energetic places.
On one hand, the more the activated doping atoms concentration, the more amount of induced carrier; on the other hand, the better the Si film structural property, such as low density of grain boundaries or inter defects, the weaker carrier scattering effects.
Thus, with the increase of RTA temperature, both dopant activation and structure property were enhanced, leading to lower resistivity of polycrystalline Si films; while, even at temperature as high as 1200 oC, it is supposed that the resulted Si films still possessed a large number of grain boundaries and inter defects, which significantly scatter the carriers, leading to the higher resistivity value compared to that of crystal Si target.

Furthermore, adding B had a significant effect on grain refinement on the SAC105 solder .
And the finer the grain size, the higher the strength and hardness of the solder alloys are [8].Furthermore, the analysis of shear strength for different components solder alloys also confirmed this.
Thus, there is a certain number of B enrichment at the interface of solder joints, as a result, it can restrain the growth of the IMC at the interface.
As shown in Fig. 8, after reflow soldering (aging 0h), the IMC at solder joints’ interface are mainly composed of scalloped Cu6Sn5 grains.
Influence of grain size distribution on the Hall–Petch relationship of welded structural steel [J].

In internal cell of At.f each 1 mol ATP produced is needed 37.2~66.69kJ energy with at least consumption 2 mol ferrous, so large number of ferrous should be oxidized by At.f to maintain its normal growth [4,5].
The first step is to make a cavity microelectrode (CME) (Fig. 1a), then the powder materials like mineral grains packed in.
The usual height–diameter ratio (hc/Øwire) was between 0.4 and 1 to make well contact between the grains and platinum and prevent powder grains could easily escape out of the cavity.
The total removal of all the grains of material was finally checked microscopically.
Fig. 7 Tafel plot of polarization curve Where IL is ultimate diffusion current, n is reaction electron number, c0* is initial concentration of ferrous ion in bulk solution, F and D is same as above.

A number of authors analyzed thermal stability of nickel monosilicide phase, NiSi, during a solid state reaction of a number of metal/Ni bilayers on Si [1013].
It is visible, that the sample consists of a number of layers.
Furthermore, formation of a number of different Ga-Ni as well as Ga-Ni-Si compounds is also possible.
The pyramidal disilicide grains are formed at the interface to Si.
The silicide grains do not grow epitaxially.

A corrosion fatigue counter is used to calculate the number of cycles.
By using laser cladding with 600 alloys in air, the fatigue test's number of cycles increased from (46427) to (55774), whereas in solution, the number of cycles decreased from (33452) to (24450).
Laser re-melting processing for alloy of turbine blades reveals fine grain size compared with grain size before laser processing which increased fatigue and corrosion fatigue resistances. 5.
The laser surface re-melting process for turbine blades alloy (st-52 alloy) increases the fatigue limits for both conditions in the air (fatigue), and environmental solution (corrosion fatigue), where the number of cycles for fatigue failure in the air was (86444) cycles with laser re-melting in air and the number of cycles for fatigue failure was (61501) cycles for corrosion fatigue with laser re-melting. 6.
Laser re-melting processing for alloy of turbine blades reveals fine grain size compared with grain size before laser processing which increased fatigue and corrosion fatigue resistances.

The wear and tear of diamond grains and matrix determine the sawing effect and tool life.
At a specific cutting depth, it will inevitably lead to periodic changes in the number of working segments at the same time, and the stress of the saw blade will also change accordingly.
However, in order to correct the quenching deformation, it is necessary to raise the tempering temperature or increase the number of times of tempering to meet the requirement of flatness.
The position ⑤ is at the cutter teeth of the saw blade, where the metallographic structure is uniform tempering troostite and a large number of dispersed granular carbonitride compounds after nitrocementation (seen in in Figure 5(f)).
In the case of severe thermal instability, diamond segments are rapidly worn away and the number of repeated use of the steel core is also reduced.

In this case, ( ) ( ))/)(exp( 1 1 0 stop r rrrFS rrr rJ r S λ−− ∂ ∂ −= ∂ ∂ −= . (3) F can be expressed as a function of the current density (Id), as � x I F d . 106.1 19−= , (4) in which � is a number (>1) relating the total number of fast species impinging the cathode and the ion current.
Different topology and grain size are observed for different cathode voltage.
The feature of zone T is competitive grain growth leading to considerable surface roughness.
In these conditions, grain coarsening occurs during coalescence of small islands with large surface to volume ratio, while grain boundaries become immobile in continuous films.
The gas total number density was calculated by the ideal gas law, the diffusion coefficient was calculated by the kinetic theory of gases and λstop is taken to be 3.5xλ, where λ is the mean free path for collision in the gas mixture.

Machining Processes There is a large number of machining processes available for making precise mould inserts for e.g.
Varying grain size and dislocations in the material are deteriorating the process stability.
Otherwise, due to the high hardness and brittle behaviour of cemented carbide materials precise grinding processes with fine-grained diamond abrasive tools are essential [13, 14].
In contrast, suitable die materials are nano-crystalline binderless Tungsten carbides with a grain size below 200 nm, having less than 0.3% cobalt and a hardness of over 2800 HV10.
Figure 5 shows tungsten carbide moulds in precision ground quality after an optimized precision grinding process with a pin-type, fine-grained, resin-bonded diamond grinding wheel.

Elevate number of increments is necessary, due to large natural process time. 3.
In a future, FEM models would be able to use material grains as element and consequently predict surface roughness.
The grains are stretched along the flow forming axis.
As exposed in [14] for steel, elongation of the worked material grains along the feed axes is noticed as well as ferrite grains stretch in the zone of huge plastic deformation.
Fish scaling is mainly due to not uniform grain size, particle inclusion and residual stresses.