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The mechanical properties are strongly influenced by grain size, among other factors.
The ductility, surface quality, fatigue and corrosion properties of extruded products, however, can considerably deteriorate due to coarse grains at or near the surfaces of extruded profiles.
Additionally, Dynamic Recrystallization (DRX, [5]) was found to affect PCG formation to a certain extent [6].
Here, the evolution of microstructure during thermo-mechanical processing is described in terms of the evolution ofdislocation density (ρ).
Sedláček: The effect of surface recrystallized layers on properties of extrusions and forgings form high strength aluminium alloys, 20.

This is because the process is independent of the rigidity and mechanical properties of the tool materials.
The discharge of the capacitance affected the pulse voltage distribution, the pulse-on period (pulse duration) and the duration of sparking.
Table 1: Factor values and factor levels Factor Levels High Low Capacitance (A) 3300pF 220pF Voltage (B) 110v 80v Tool dia.
The above elaborations suggested that the factor (iii) would be the dominant mechanism in generating the possible ovality of the holes.
The outcome is affected by the energy input to melt and evaporate the specimen material and the ease of squeezing out the melt from the hole when the electrode is being retrieved.

At the same time, Ti alloys are widely used for the airplane because of their excellent comprehensive properties.
The tensile machine is CSS-1100 type electronic mechanical one.
As shown in reference 3, Ti-SP2500 alloy possess favorite mechanical properties at ambient and moderate temperature.
Even in the condition of low temperature or high speed deformation, the grain-boundary sliding is the controlling factor.
Figs.8(a) and 8(c) are the microstructures of un-deformed parts which are only affected by temperature and time.

The wastewaters containing dyes diminish the transparency of the water and affect the growth of the organisms in the water [1].
Large specific surface area, chemical and mechanical stability, layered structure, high cation exchange capacity (CEC), etc., have made the clays excellent adsorbent materials [5].
As can be seen from Fig. 2, the microstructure and surface properties of the sepiolite and the rectorite are quite different.
The essential characteristic of a Langmuir isotherm, related to the isotherm shape, can be expressed in terms of a dimensionless constant separation factor, also called equilibrium parameter, RL, which is defined according by the following equation [13]: RL=1/(1+kbC0) (4) The value of RL indicates the nature of the adsorption process to be either favorable (0< RL <1), unfavorable (RL > 1), linear (RL =1) or irreversible (RL = 0).

Introduction Fracture strength is one of the most important mechanical properties for brittle materials such as ceramics.
In this simplified test, the time to fracture was around 1-2 seconds, so that slow crack growth did not affect the strength data.
We can see R2 (square of correlation factor) is larger than 0.9 in all plots, indicating that data fitting is very good.

Chang 1, b 1 Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan a yytsai@ntu.edu.tw, b r95522719@ntu.edu.tw Keywords: abrasive, polymer, soft particles, hard particles, PMDEDM Abstract.
Powder-Mixed Dielectric Electric Discharge Machining (PMD-EDM) has been generally regarded as an effective way to improve the surface properties, due to increasing the spark gap and widening the discharging passages [2].
It was found that the concentration, size, density, electric resistance and thermal conductivity of powders would affect the machining performance significantly.
Table 1 Experimental parameters of particles mixed dielectric Working Factor Working Condition Electrode Copper Work-piece Stainless steel (SUS304) Discharge Voltage 250V Capacitance 0.01μF Rotation Speed 200 rpm, 2000rpm Working Fluid Silicone oil Particles soft particles Starch (Mw~107~10 9) Polyaniline emeraldine base (Mw~65000) Polyaniline emeraldine salt (Mw>15000) hard particles Aluminium(Al) Silicon (Si) Alumina (Al2O3) Concentration of Powder 0g/l, 2g/l, 6g/l, 10g/l Abrasive Alumina (Al2O3), 6g/l The parameters used in the experiments were listed in Table 1.

Introduction Silicon carbide (SiC) is an excellent material for high-power and high-temperature applications due to its attractive mechanical and electrical properties.
As an order of magnitude is observed for the SCR values, according to the post-implantation annealing temperature, the results let us suppose that the activation is severely affected by the temperature.
(1) Where ND is the donor concentration, g is the degeneracy factor, NC is the effective density of states in the conduction band, kB is the Boltzmann constant and T is the measured temperature in Kelvin.

Study of the precursory rules As they are naturally heterogeneous objects, the mechanical properties of coal and rock are discrete [7].
Based on the above results, the destruction of the sample surface was mainly affected by the relative sliding component as loading began, and the relative tension component did not participate significantly.
As the load continued to increase, the relative tension component increased rapidly and became the dominant factor in the deformation damage, while the relative sliding component changed more gently.

The Double-K fracture model The Double-K model contains two material parameters; the first is called the initiation stress intensity factor KIcini, which defines the onset of cracking, and the second the unstable fracture toughness KIcun, which defines the onset of unstable cracking or failure.
Since in the Double-K model it is necessary to use proper compliance and shape functions according to the test configuration and material properties, these functions were determined based on numerical simulations using the final element method according to [4].
wc [mm] Volumetric dosage of fibres 0 % 0.5 % 1.0 % 2.0 % H0 0.217 (9.9) | 1.00 − − − H1 − 0.788 (8.9) | 3.64 2.180 (13.9) | 10.1 3.246 (12.6) | 15.0 H2 − 0.733 (17.7) | 3.38 1.636 (8.7) | 7.55 − H4 − 0.657 (15.6) | 3.03 − 4.049 (34.8) | 18.7 Summary The volumetric dosage and length of hemp fibres added to the plain concrete matrix significantly affects all its mechanical fracture parameters, whereas the fibre dosage has substantially more influence than its length.

The quality factor shows a similar behavior by a variation of Id0.
The limiting factor is that there can only be one discharge at a time.
For the current investigations, vitrified bonded wheels are selected due to their good dressability and profile holding properties compared to other bonding systems [1].
Due to the mechanical load on the vitrified wheel layer during the dressing process, breakouts occur at the profile tip, where the structure strength is not high enough to withstand the dressing force.
A further increase in the dressing parameters does not affect a further increase in the specific material removal rate Q'sd.