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EDS mapping of the elements showing some Mo and Ni compounds segregating in the consolidated sample In the figure 5 the microstructure of the sample after spark plasma sintering process reveal dispersoids near the grain boundary area and solid solution formed after the process of mechanical alloying and consolidation.
The VEC number of this alloy indicates the formation of FCC phases in amounts larger than BCC and the diffraction pattern verify this theory [9].
The powders were consolidated via spark plasma sintering and the microstructure study realized on the consolidated sample revealed a homogenous structure with two solid solution phases and fine components segregating at the grain boundary.

Further, the core diameter should be at least three times larger than the largest aggregate grain size.
That is why a diameter of 75 mm is an optimal compromise considering the density of reinforcement and the aggregate grain size.
If it is not possible to use cores with a diameter of 75 mm, cores with a diameter of 50 mm can be used but the number of tests must be higher.

For important compaction energies, exceeding the optimal one, the over-compaction can lead to the disintegration of grains and then the granular structure is not as resistant as the initial one.
In HEB 195 [14], the choice of the press depends on the desired pressure and the number of units produced per day.
Three specimens were prepared for each number of blows (25, 56, and 100 blows) (Table 4).
Using a scanning electron microscope (SEM), it is shown that the grains, after stabilization, form a honeycomb structure which is a result of the hydrates precipitation on the surface of the grains.
Table 8 shows the difference between the RE technique and PEB in terms of execution time, materials, and number of workers.

The results showed that changes of PH value has significant effect on the specific gravity of soil grain, the limit moisture content , maximum dry density, and strength characteristics of loess.
Especially with the number of motor vehicle accelerating, the city build expedited and the serious air pollution, acid rain increased [1], the problem of loess contaminated by acid is prominent.
The possible reasons are as follows: with the increase of acid concentration, a large number of cations will change the chemical balance in soil. thickness of adsorbed water will reduce ,the diffusion layer to thin, plasticity of soil are weak, so the liquid, plastic limit and plasticity index will decrease.
In the liquid limit of soil, containing a large number of water molecules, the colloid ion precipitation reduced, it has little effect on the liquid limit.

A number of MWNTs were observed pulled out from the alumina matrix.
The alumina grains became more rounded and more pores (indicated by arrows) could be found in Fig.3B.
On the fracture surface, MWNTs were observed pulled out from the matrix, but their number was relatively less compared to the number of MWNTs in Fig.2B.
This lower density and fewer numbers of pulled-out MWNTs caused the catastrophic decrease in bending strength.

On the basis of numerical methods, the mutually dependent parameters or variables are solved in the finite number of the nodal points of the discretization mesh in calculated domain.
The numerical methods enable us to find the solution of the physical variable for the specific number of discrete sites (nodes) in relation to the selected differential mesh (finite element mesh) and it is in connection with the whole domain and surface part of the created geometrical model.
The basic principle of FEM is based on the fact that the arbitrary continuous variable (e.g. temperature, velocity, etc.) is substituted by discrete model which is defined as a set of continuous functions (polynomials) with reference to finite number of sub-domains (elements).
The searched functions are approximated by polynomials in the boundaries of the each one sub-domain in such a way that the coefficients of the approximating polynomials are expressed by the values of searched function in the finite number of the nodal element points.
After the evaluation of the nine samples under the different stresses on the basis of the temperature and time effect, it can be concluded that stainless steel (designated as STN 17 248) is able to operate for short time (for ~1 hour) at 900°C, but when the holding time is increased at the same temperature, the grain coarsening is observed and it can have negative influence on corrosion resistance as well as mechanical properties of the tested material.

Title of Publication (to be inserted by the publisher) Scaffold Fabrication The polymers foams were impregnated with the following suspension: 88,4 g of TiO2 powder (Kronos TiO2 No 1171, Kronos Titan GmbH, Leverkusen, Germany) with a median grain size of 0.3 µm mixed with 25,8 g deionised water.
Results Foam structure The macrostructure of the sintered scaffolds is characterised by a fully open structure for both ppi-numbers, although a very low number of closed cells is always present.
The tortuosity, which was measured in the mercury intrusion meter, was several factors higher for 60 ppi scaffolds compared to 45 ppi and therefore do also explain the lower permeability for higher ppi-numbers.
The pore size is easily adjusted by using polymer foams with different ppi-numbers.

Fig. 3 Microstructural crack exposure Derived microstructure with opened crack is shown, and is clearly how crack propagates through the grain boundaries.
a) b) Fig. 4 Specimen and testing configuration for: a) CT and b) SENB specimen Fig. 5 shows dependence between crack length, a, and the number of cycles, N, for different load ratios (R=0.1 and R=0.5).
a) b) Fig. 5 Number of cycles vs. crack length for: a) R=0.1 and b) R=0.5 load ratio Compliance test, as well as crack resistance curve is shown on the picture bellow (Fig 6).
Modelling of damage initiation and growth The direct cyclic analysis procedure from Abaqus/Standard is used in this work to compute the stabilized response of the structure directly [7], without need to compute a number of sequential cycles that would lead to such stabilized cycle.
The cycle number in which damage is initiated is written in the form: , (1) where c1 and c2 are material constants.

The titanium substrates were placed in the reactor so that sample number 1 was located in the middle of the cumulative jet, samples number 2 and number 3 on the periphery at equal distance from the center.
The average crystallite size for sample number 1 estimated by Scherrer formula is: · crystallites TiC – 33 nm., · crystallites of HCP titanium – 16 nm., · crystallites of BCC titanium – 7 nm.
This indicates the presence of the transition zones where titanium grains of substrate are mixed with the coating material.

In order to ensure the safety of high strength steel components, it is necessary to conduct further studies on the fatigue behavior and fatigue mechanisms of high strength steels at the numbers of cycles from 108 to 1012.
They show that fatigue failures take place at the numbers of cycles above 107 even 109, which means traditional fatigue limit does not exist.
The shape of S-N curve could be affected by specimen shape, loading characteristics, inclusion size and number of samples.
They show that the area of ODA and number of cycles are related to hydrogen content.
In the interior, a strain concentration will somewhere exist between grains at a location where: (i) a small inclusion or precipitate is lodged between two or three large grains; (ii) long grain boundary; (iii) a combination of (i) and (ii).In interior strain concentration zone, it is possible for a very short Stage Ⅰ- and then a Stage Ⅱ-oriented type of crack to initiate and propagate.