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.%) were tested as candidate materials for tribological applications using a twin-disc wear test rig, to measure their wear and frictional properties under variations of number of cycles (103 to 106), load (300–600 N ) and velocity (0.785 m/s, 1.57 m/s and 2.35 m/s), all at a slip ratio of 2%.
The grade of PBT was the commercial Crastin 6130 NC010 (as supplied in grains by DuPont – table 1).
The grains of PBT were dried before molding in order to eliminate undesired humidity, the residual humidity content has not to be over 0.04 % (wt).

SEM/EDS analysis indicates that: (i) the matrix region (A) of this composition contained Mg and small amount of Al; (ii) the grain boundary region (B) contained Mg as well as Al and Sr.
Al4Sr phase formed during eutectic solidification process is located in the grain boundary region of the Mg and appears to be lamellae.
Secondary Phase The liquidus temperature and the number of transformations of sample 12 did not show good agreement with the thermodynamic predictions.

Mechanism of stock removal in this process is a result of spark synergy of electrical discharges occurred between metal binding of grinding wheel and machined surface layer and abrasive grains machining of cutting surface of grinding wheel (CSGW).
An essential problem concerning AEDG process is on the other hand the heat generation in the contact zone of the grinding wheel and workpiece, caused by machining work of abrasive grains of the grinding wheel and the energy spark discharges in electro erosion processes.
The increase of the grinding temperature due to heat producing action causes a number of unfavorable changes on the surface layer of the workpiece.

The dynamic process of crystallisation and recrystallisation during the oxidation modifies the oxygen diffusion coefficient by decreasing the grain size distribution and finally the number of short circuit paths in the oxide layer along the grain boundaries.

The bed was composed of powder mixture of Al (99.5% purity, grain size 200 μm)-silicon (97.5% purity, grain size about 40 μm) as metallic donor.
Equivalent circuit of protective scale model Taking into account the dispersion effect, a constant phase angle element CPE = [Q(jω) n] -1 was used to describe the element Cdl and Cox in the fitting procedure, where j is the imaginary number, Q is the frequency independent real constant, ω= 2πf is the angular frequency (rad/s), f is the frequency of the applied signal and n is the CPE exponent[8].

Furthermore, large numbers of the sample are more needed for further analysis to present valid equations with having a high correlation.
Dwivedi, Prediction of Compression Index (Cc) of Fine Grained Remolded Soils from Basic Soil Properties, International Journal of Applied Engineering Research. 11, 1 (2016) 592-598
[9] A.Sridharan and Nagaraj H.B, Compressibility Behaviour of Remoulded, Fine-Grained Soils and Correlation with Index Properties, Canadian Geotechnical Journal. 37 (2000), 712-722

The mechanisms of both swelling and shrinkage in expansive soils are complex and they are influenced by a number of factors.
Fig. 1 X-ray diffraction patterns of the soils used in the test program Table 1 Physical properties of expansive soils studied Liquid limit (%) Plasticity index (%) Shrinkage limit (%) Grain size distribution Optimum moisture content (g/cm³) Maximum dry density (%) Free swell (%) Sand(%) Silt(%) Clay(%) 56.1 25.5 7.44 15.6 44.5 40.9 18.2 1.83 51.5 Initial moisture content and initial dry density are important parameters in affecting the swelling behavior[5-6].
Swelling behaviour of compacted fine-grained soils.

In the last years, an increasing number of papers was published on FSW of magnesium alloys.
It was found that optimum level of heat generation, formation of finer grains, and higher hardness are the main reasons for the superior tensile properties of the joints.
The absence of defects in weld region, presence of very fine equiaxed grains in the weld region and higher hardness in the weld region were identified as the main reasons for superior tensile properties of these joints.

Stress-strain values were stored and processed to determine cyclic stress responses and plastic strain amplitudes as a function of the number of cycles.
Dynamic recrystallization It is important to determine the microstructure evolution during industrial hot rolling, which can predict the mechanical properties of the hot-rolled products, design the most effective hot rolling process to obtain the customer requirement, reduce the costs for routine operations and develop new products[12].Recrystallization is a process of fundamental importance in the thermo-mechanical processing of metals and alloys, which can result in grain refinement, reduce deformation resistance and directly affect the microstructures of the final product[13].
However, the mechanisms responsible for the grain refinement of austenite have not yet been clearly described and identified.

As indicated in Figure 2, this difference in cooling or solidification rates between the thin and thick sections significantly impacts both their grain structure and properties.
However, the detection of the relatively high Al (10.07 at%) content in the Mg-Al-Zn phase and low Al level (4.28 at%) in the primary α-Mg grain of the 20-mm section implied that the slow cooling promoted the migration of Al from the primary phase to the micron Mg-Al-Zn phase during solidification.
While Figure 11(a) indicates that pores in small sizes are visible in the thin wall (6 mm), Figures 11(b) and (c) show a noticeable number of large pores in both the 10 mm and 20 mm specimens, respectively.