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Graphite particle metal matrix composites which exhibit superior tribological properties such as low friction, low wear rate and excellent seizure effects [4].
The CCD is an alternative approach that can be used study factors at five levels in lesser number of tests compared to the full factorial design [7, 8].
It is evident from the main effects plot as given in Figure 2 that the factor speed is not statistically significant affecting the mean resultant force.
Main Effects and Interaction Plots Table 3: Analysis of Variance for Hybrid Composites using Adjusted SS for Tests Conclusions: From Figure 2 it can be concluded that a Feed (B) and Depth of Cut (C) are the predominant factors affecting mean resultant force.
References [1] “Production and properties of SiCp-reinforced aluminium alloy composites”, Y.

In addition, factors of environmental pollution such as acid rain, that causes corrosion, have the tendency to increase.
But spot welded structure strength is affected by dampness and environment temperature.
Table 1 and Table 2 show its chemical and mechanical properties.
It is shown that irregardless of temperature change the clearance in specimens are important factors in influencing tensile load.
This damage is affected by the surroundings that contact material inevitably in use and by various loads and external forces.

Even in their simplest topological forms containing randomly dispersed equiaxed particles, such composites are rather complex materials, incorporating interfaces with a wide range of properties and internal residual stresses due to processing or thermal misfit.
The ratio between the averaged strain energy release rates (or related stress intensity factors) at the deflected and the undeflected crack front expresses the relative amount of toughening [3,4].
This can be done by numerical computing of local k1, k2 stress intensity factors at the elementary kinked crack tip and by using eq. (1).
The magnitudes of the vectors are proportional to the Keff -factors in respective crack tip positions.
Fig. 2: The map of effective stress intensity factors Keff within the investigated area a) small holes, b) small rigid particles, c) large holes, d) large rigid particles.

The choice of solvent, control of base volume, feeding methods and other factors were optimized , toluene/isopropanol (85/15) is the best solvent .
Using FT-IR, elemental analysis, TG, DMA, X-ray and other means, we compared the structure, degree of substitution, the crystallinity, thermal stability, dynamic mechanical properties, dielectric properties and acid and alkali resistance between the CECs by solvent method and traditional method.
The degree of substitution (DS) is usually considered to be one of the most important factors in affecting the properties of CEC[2].
Elemental analyses were performed using Element Vario Micro Cube (Germany), degree of substitution and nitrogen content can be measured by elemental analysis as following equation[19]: Dielectric properties were tested by Agilent 4294A impedance analyzer, 0.5cm × 0.5cm small square thin CEC films coated with conductive silver paste adhesive on both surfaces were made as samples, samples’ dielectric properties can be evalued by the value of dielectric constant ε .
Dynamic mechanical thermal performance were analysised by TA U.S. companies DMA2980 dynamic mechanical thermal analyzer .Membrane material samples sized 30 × 6 × 1mm, test temperature -100 oC -200 oC, test frequency 1 Hz, amplitude of 10 μ, heating rate 5 oC / min.

Based on the structural characters of roof in fully mechanized top coal caving, mechanical analysis, mechanical calculation and simulation experiment were used to explore the particularity of roof structure in fully mechanized top coal caving.
Comparing with the general fully mechanized mining, the top coal caving has two different basic factors, mining height and the properties of roof.
The change of mining height directly affects the height of caving zone, and the change of roof’s properties affect the transfer mode form overlying strata structure to support’s force.
In this paper, the change and change form of overlying strata structure, determining working characteristics and reasonable support resistance of hydraulic supporting frame, and the relationship between these factors, parameters and properties of mining height and roof were systematically analyzed in the condition of fully mechanized top coal caving.
However, because of the change of mining height and roof properties, it is obvious that the support pressures were difference between the fully mechanized top coal caving and general fully mechanized mining.

Nonetheless, the stringent requirements on the overall mechanical properties of the welded joint should be met [1].
Nuclear steam turbine low pressure rotors having a weight of 200 tons, which are designed to operate at the rate of 1500rpm (half-rate groups) in high-temperature water vapor for 60 years, are the key parts affecting the safety reliability of the power generator groups[2].
Due to the complicated welding heat process, inhomogeneity in compositions, microstructures and mechanical properties of the welded joint is inevitable[3].
Thus, the overall mechanical properties of the welded joint are critical for the reliability of rotor.
Among the existing researches on the overall mechanical properties of structures with long life, many concentrated on the fatigue crack initiation and fatigue crack propagation and corresponding affecting factors in materials with homogeneous microstructures[4].

In order to tackle the problem, new and scrap Mo fibers are added to PC to improve its mechanical properties [4].
Fibers can restrain deformation of matrix, thus improving the mechanical properties of MFRPC.
Influencing factors of interface bonding property.
Therefore, appropriate mass ratio of resin and hardener, the addition of coal ash can increase the density of interfacial transition zone, improve area properties around fiber, and can also enlarge wettability, contact area, interfacial friction of fiber-matrix and aggregate-matrix, thus effectively improving interfacial bonding properties [6,7].
Reinforcing Finite Element Analysis of New And Scrap Fiber Surface state, one of microstructure characteristics of fiber, is not only the important factor to affect interface bonding property but the prime determinant to influence fiber reinforcing effect.

The results indicate that the amount of ZrO2 additive is one of the key factors controlling of leucite crystallization.
The results showed that the mechanical properties of leucite glass-ceramics increased as the amount of ZrO2 was increased.
As the amount, average crystal size and structure of the leucite phase directly affect the thermal and mechanical properties of the final composite material; suitable technology of its preparation was necessary to be developed [5].
Characterization and Mechanical Property Tests of the Glass-ceramics.
The introduction of ZrO2 is beneficial to the improvement in the mechanical properties of the leucite glass-ceramics.

The methods of obtaining these properties decides the project design’s safety and reasonable.
In this paper, at first, the author analyzes the size effect factors.
Rock mass failure strength and size effect Size effect exists in natural among many factors affecting to rock mass strength which directly affect the strength parameter used to project.
But it has not considering the rock mass creep characteristics, namely, the properties of rock mass is the function of time.
We only know the rock mass strength in qualitative based on the uniaxial compression strength which is one of the factor affecting rock mass stability.

The estimation of damping factors is of interest in most branches of engineering sciences.
It can also be seen from the data that the riveted joint loss factors are generally lower than those from the bolted joint.
The loss factors for the noncritical modes (3, 4, 5, 6, 8, 10) correlate well with the previous data shown in Fig. 5.
The general trend for the data is that the loss factors reduce for the higher modes.
International Journal for Mechanical Science, Vol. 9, 1967, pp. 743-766