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It is also found that water play as a key factor in CMP.
Silicon nitride (Si3N4), especially, is considered as the most promising material for high speed, high temperature and high precision bearing for jet engine, high precision machine tool and apparatus due to its desirable properties [1].
A critical factor affecting the performance and reliability of Si3N4 balls is the quality of the surface after final polishing, for that ceramics are extremely sensitive to surface defects resulting from machining processes owing to their high hardness and inherent brittleness.
Experimental Set-up and Procedure Table 1 lists the experimental conditions for finishing of Si3N4 balls, and Table 2 lists the mechanical properties of Si3N4 balls in this study.
Table 1 The experimental conditions Si3N4 balls Abrasive Slurry based fluid Abrasive concentration Load Plate rotation Polishing time per trial Diameter: Ø5mm Roughness (Ra): ~60nm B4C Al2O3 SiO2 Fe2O3 Cr2O3 CeO2 Water 10-30% wt ~0.5N/ball 30rpm 120min    Table 2 Mechanical properties of Si3N4 balls Properties Value Density Hardness Young's modulus Poisson's ratio Compression strength Bend strength 3200 Kg/m 3 HV 1500 310 GPa 0.26 >3500 MPa 600 MPa The surface roughness was measured by Pethometer S2 (Maer Co.)

Due to the nature of solid rocket propellants it is important to know their thermal and mechanical properties which may affect the proper operation of the rocket engines.
A powerful technique for determining mechanical properties of solid rocket propellants is the dynamic mechanical analysis [10].
These properties are dynamic storage modulus E’ which represents the elastic properties of material, dynamic loss modulus E’’ which represents the viscous properties of material and tan(d) = (E’’/E’) which represents the damping of material [3].
Mušanić and Sućeska [6] have studied the dynamic mechanical properties of double base rocket propellant artificially aged at temperatures of 80, 85 and 90 °C, in order to detect and quantify changes in the dynamic mechanical properties caused by ageing, and to investigate the possibilities for the prediction of service lifetime.
In the near future, further study of thermo-mechanical properties of different types of solid rocket propellants are planned.

The effect of such processing on mechanical and corrosion properties of aluminum alloys is shown.
SPD effect on mechanical and corrosion properties Another important factor determining the advantages of using SPD at forging is its influence on mechanical and corrosion properties of aluminum alloys.
Let us compare the mechanical and corrosion properties of alloys after SPD combined with hardening and those after ST.
The effect of treatment on mechanical properties.
The effect of treatment on anisotropy of mechanical properties.

The chemical composition and mechanical properties of this material is presented in Table 1.
Chemical composition and mechanical properties of brass: JIS H3250 C3604 Chemical composition (%) Cu Pb Fe + Sn Fe 57.0-61 1.8-3.7 <1.2 <0.5 Mechanical properties Tensile strength, MPa Elongation, % Hardness, HV 335 20 80 Machine and Cutting insert.
The experimental factors and levels are shown in Table 2.
Factors and levels in dry turning.
The factors that significantly affect the surface roughness are speed and feed.

Except mechanical, viscoelastic and thermo gravimetric properties, transport properties like electrical conductivity, thermal conductivity and water transport properties were studied for the first time.
Here various factors such as concentration and aggregation of fillers, processing technique of composites and distribution of fillers in the matrix affect the electrical conductivity and percolation threshold of the composite.
Again some geometric factors like filler aspect ratio are the most important property to determine the percolation threshold.
Table 1 Mechanical properties of different types of nanocomposites.
Takeichi, Studies on thermal and mechanical properties of polyimide–clay nanocomposites, Polym.J. 42(2001) 3399-3408

This is especially noticeable in Mechanical Alloying (MA) which is used for producing a wide range of metastable materials (supersaturated solid solutions, amorphous phases, nanostructures) with unique properties.
The model includes basic physical factors that affect diffusion, such as generation of non-equilibrium point defects by gliding screw dislocations during deformation and their relaxation in periods between impacts.
At present, MA is used as a versatile means for producing far-from-equilibrium powder materials with unique properties, such as supersaturated solid solutions, quasicrystalline and amorphous phases and nanostructures (see reviews [2-4] and literature cited therein).
Optimization of MA processes and development of advanced materials with superior properties necessitates the creation of mathematical models of MA.
For example, Shtremel' [8,9] completely rejects the role of diffusion in MA basing on the classical diffusion theory which, however, does not account for the process-specific physical factors.

Fig.1 IR spectra of a-G0, b-G30 and c-G30M6 Mechanical properties.
Figure 2 shows the mechanical properties of samples in different molding temperature.
When molding temperature is lower, cross-linking process cannot be fully completed, which lead to poor mechanical properties.
With the rise of temperature, the degree of cross linking increases, the mechanical properties also increased.
These two factors contribute to the increased mechanical properties of the cottonseed protein plastics.

It possess such properties as high damping, the ability to absorb the impact energy, resistance to high or low temperature, slow ageing, and so on.
In the field of engineering, we wish to achieve appropriate metallic rubber structure effectively and quickly, but there is great distance between theoretical description and practical engineering, and the distance is a key technique problem affecting metallic rubber structure used widely.
The properties of metallic rubber directly affect those of metallic rubber isolator.
Therefore if density and shape factor of metallic rubber were given, but heat treatment technlogy was different, each coefficient of nonlinear constitutive relationship of the material were obtained, and thus the material could meet the mechanical properties demands, which lays a theoretical foundation for designing and manufacturing the material.
If density and shape factor of metallic rubber were given, and heat treatment technology was different, different coefficients of nonlinear constitutive relationship of the material were obtained, and thus the material could meet mechanical properties demands, which lays a theoretical foundation for designing and manufacturing metallic rubber.

Physical properties (humidity, density, temperature), the range of values of which depends on the engineering and design, operating conditions that affect the mechanical properties (angle of internal friction, specific adhesion) – the ability to resist fracture.
Most scientists attribute to the factors of instability precisely the properties of waste and the structural features of the structure of the disposal facility, as well as external ones, such as an earthquake, excessive precipitation, recycling of leachate, earthworks, fire, explosion of biogas, and the like.
Slope geometry is one of the determining factors affecting the geotechnical properties of waste and slope stability [12].
Mechanical properties (angle of internal friction, specific adhesion) – according to DSTU B V.2.1-4-96 (GOST 12248-96) “Bases and foundations of buildings and structures.
Carvalhod Mechanical Properties of Municipal Solid Waste.

Vacuum diffusion bonding characteristics of GH4169, interface bonding holes and mechanical properties of the joints were investigated.
Vacuum diffusion welding is known to play an important role in aerospace, military and automotive industries because of its excellent mechanical property[6-7].
Many factors affect the quality of diffusion bondings, including temperature, time, pressure, surface preparation and using of interlayers.
The relationship between microstructures of interfaces and mechanical properties of bonding joints are discussed.
In order to achieve the joint with intimacy of contact and excellent mechanical property under low welding parameters, diffusion bonding of the GH4169 with Cu interlayer was investigated.