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The mean DRX grain diameter was estimated to be about 6 µm and this value appeared to remain approximately constant during straining, in good agreement with the published data [1,2].
The driving force for this process arises from a reduction in the total boundary energy.

A 6-channel analogue data acquisition system was developed to analyze and record the pressure signals.
The gas channels also result in the reduction of heat and mass transfer at the surface.

The cutting forces component FY, feed force component FX and radial or thrust force component FZ were measured on line by Kistler dynamometer 9265 B with data acquisition system.
When the shear angle is increased, very thin chips are produced due to heat as well as by the reduction in material strength.

SEM-EDS (Energy Dispersive Spectroscopy) analysis carried out on the first d-ferrite grains formed show that, within this phase, there is a drastic reduction in the nickel and copper, and an increase in chromium and molybdenum content with respect to the surrounding austenitic matrix.
From eqs (1)-(2): (5) From the experimental data, and assuming an isotropic volume change in the sample, the atomic volume of the sample (V) can be expressed as: (6) With V0 the atomic volume at the start of the transformation.

The analytical background, used in the electrical data analysis, was as follows: a) The Arrhenius expression [2,9,15] has been used to fit the temperature dependence of the ac and dc conductivities (Eq.1):      −= Tk E Baexp0σσ (1) where σ0 is a pre-exponential factor, Ea the activation energy, kB the Boltzmann constant and T the temperature for the ac and dc values; b) The complex permittivity, ε*=ε´+jε´´, was calculated through the sample impedance measurements, knowing that Z *=1/(µε*) (where µ=jωC0, ω is the angular frequency, C0 the admittance of the empty cell and 1−=j ) [15] Results 10 20 30 40 50 60 70 80 2 theta Intensity (arb. units) 700 650 800 750 x x x x x x x x x - NaNbO3 Fig. 1 XRD spectra of the heat-treated samples.
The 800ºC treated sample presents, comparatively with the 750ºC sample, a reduction in the particle number but an increase in their size (Fig.2d).

In this study, we have adopted the Rietveld’s powder structure refinement analysis [15-19] of X-ray powder diffraction data to obtain the refined structural parameters, such, lattice parameters etc. and microstructure parameters, such as particle size and residual micro strains (r.m.s) of lattice.
This can be explained by the important reduction of the crystallite size and the introduction of an important amount of lattice defects at this stage, which enhances the diffusivity of the Al atoms into the Ni matrix.

For example, significant strengthening at room temperature was observed in a range of commercial aluminum-based alloys processed through ECAP but each alloy, without exception, exhibited a major reduction in the ductility [4].
First, the testing strain rate is not as high as the strain rate used for the data shown in Fig. 2 which marked the onset of higher strength and good ductility.

Fig. 1: Assessment of the surface quality after coating process [Audi] The essential reduction of costs, weight, fuel consumption and CO2 emission, is only possible through consequent combination of material-, shape-, manufacturing- and construction lightweight concepts.
Furthermore, the anisotropic and hardening characteristic values as well as the young’s modulus according to Fig. 4, are described in temperature depending data.

Accelerating hydration of expansion components results in the disintegration of partial particles and the reduction of grain size of steel slag under hydrothermal condition.
Results and Discussion Content of free CaO is a very important data for volume stability of steel slag because of solid-phase volume increment of 97.72% when it hydrated.According to the equation (1), the content of free CaO can be calculated as shown in table 1.

According to single, dual-pass experiment data, we establish multi-pass experiment project.
Table 3 Experiment technology of multi-pass compression tests Roll pass Distortion temperature ˚C Relative reduction / % Strain velocity /s-1 Time between passes/s program a b c a b c a b c 1 1060 45 45 45 3.673 3.673 3.673 2 980 40 45 45 7.539 9.004 9.004 15.49 15.49 15.49 3 940 38 40 35 15.111 18.482 15.475 4.65 4.26 4.26 4 900 38 35 35 35.741 38.447 34.097 2.88 2.56 2.77 5 860 32 27 32 59.068 54.723 58.408 1.79 1.66 1.80 2.3.2 Result analysis of multi-pass rolling Fig.6.