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In addition, although a small number of samples were tested, the results for alloy C shows good repeatability.
In the current alloys, austenite is present both a blocky morphology located on prior austenite grain boundaries and as thin laths.
Since some hydrogen is expected at block interfaces on the prior austenite grain boundaries and at film austenite interfaces, it is perhaps not surprising that both intergranular and transgranular fracture paths were seen in most specimen fracture surfaces.

The specimen rotation allowed to increase the numbers of grains analyzed, limiting any texture effect.
Mean b grain size was 350 µm.

The increasing number of cars, especially those with Diesel engines, and trucks creates a constant threat to the environment.
The occurrence of characteristic high frequency "double arc" in the complex plane plot is usually attributed to granular structure and division between grain interior and grain boundary conduction [6].

The number of stable nuclei n is a function of temperature (T) following the equation:         kT G An exp (3) where A is a constant, GV is the critical free energy change, K is the Boltzmann constant.
Thus, at higher temperatures, we get few nanoparticles with larger grain size.
On the other hand, at lower temperatures, the nucleation rates are high and due to lower atomic mobility growth rates are low, which results in many small particles with smaller grain size.

Si feedstock of commercially available electronic-grade quality (grain size ~ 10 mm) was filled in a Si3N4 coated silica crucible with inner diameter and height of 60 mm and 100 mm, respectively.
Axial slice of the same crystal revealing the typical grain structure of mc-Si (c).
The roman numbers denote the process steps: I - Heating, II - Homogenization, III - Directional Solidification, IV - Cooling.

The main developments with these alloys are concerned with processing, to control the grain structure and properties, and to achieve nearer to net-shape products by non-chip making methods.
In the as-received conditions, the microstructure is composed of primary α-phase (equiaxed grains) and secondary α-phase (platelets) with a very little amount of β phase.
Due to the strain and strain rate gradients, strain, strain rate and stress are derived at the surface of the specimen with the help of equations ( 1 ) and the Fields and Backofen [2] relation ( 2 ), which assumes isothermal test and isotropic material. 2 3 = & & N r L π ε and 2 3 = N r L π ε ( 1 ) ( )3 3 3 2 m n R σ π = Γ + +% % with ln ln N m N ∂ Γ = ∂ % & ln ln N n N ∂ Γ = ∂ & % ( 2 ) where r is the specimen radius, L the length, m% and n% the torque sensitivities to the velocity of rotation and to the number of revolutions, respectively.

Table 1 The cutting forces and the tool life Experiment number Cutting parameter Cutting forces Tool life Dept of cut ap(mm) Feed rate f(mm/rev) Cutting speed Vc(m/min) Fx (N) Fy (N) Fz (N) Time (min) 1 0.2 0.10 50 63 105 82 40 2 0.2 0.15 60 29 112 121 33 3 0.2 0.20 70 25 142 155 27 4 0.3 0.10 60 54 108 110 30 5 0.3 0.15 70 79 171 137 20 6 0.3 0.20 50 20 110 225 23 7 0.4 0.10 70 35 113 120 29 8 0.4 0.15 50 57 172 165 25 9 0.4 0.20 60 107 220 235 14 Results and discussion Results of orthogonal cutting tests are first presented in terms of cutting forces and wear patterns.
The carbide grains and the cobalt binder of the insert are worn at the same rate.
Chipping may appear when friction force pull out the WC grains from the tool surface.

The grain size of the heat-treated alloy grows to more than 100 mm, and as a result, its hardness decreases.
As the beam current increased, the number of re-melting increased since the width of the weld bead increased, as shown in Fig.5.
The grain sizes of the Co-Cr-Mo cast alloy were large, at 100 mm or more, hence the intensity ratio of each of the peaks did not match the ASTM data.

It could be seen that the particle size of samples decrease with the doping content increased, indicating that the doping could further restrain the grain growth of TiO2 at a certain extent.
As shown in Fig. 3, the final TiO2-coated film electrodes with flat surfacing had a uniform porous structure, like a sponges made by connecting between the TiO2 particles, whose average grain diameter was about 25 nm.
The decrease of open circuit voltage of cells is because that, with the increase of the film thickness, the surface area in TiO2 flim increased, corresponding to that the numbers of surface defect states also increased, which made the transportation of electron back easily and increased the recombination of electron on conduction band with 3I− in the electrolyte, resulting in a lower open circuit voltage [8].

Introduction Considerable number of automotive companies place great emphasis on reducing vehicle weight.
Molten metal was purified with salt AlCu4B6 before casting and was not modified or grain refined.
The experimental material was not modified or grain refined therefore eutectic Si was observed in a form of needles on scratch pattern of as-cast samples (Fig. 1a) (on deep-etcher samples in a form of large hexagonal platelets) (Fig. 1b).