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The (S/N) response analysis and Pareto analysis of variance (ANOVA) are used to identify the most significant parameters affecting the surface roughness.
The factors and levels are specified in Table 1.
The feed rate and the depth of cut are also significant machining parameters affecting surface roughness.
Consequently, this would reduce the cutting forces, which is required for better surface roughness as well as to preserve material properties against residual stress and change in micro hardness at the subsurface.
Ceramic and Glass Materials: Structure, Properties and Processing. (2008), Springer. p. 158

Obtained relationships between the microstructure characteristics and mechanical properties were described using physically based models and used to establish a material specific database for prediction of the mechanical properties from X-ray diffraction data.
To a great amount, the microstructure influences the mechanical properties of the steels and is strongly influenced by technological factors.
An additional benefit is the fact that the effects which can be measured by means of the XRD are directly related to the steel’s mechanical properties.
During wire drawing, the strengthening mechanism switches from microstructure refinement effects to strain hardening effect mainly responsible for the materials mechanical properties development.
Additional microstructure information (about residual stresses and preferred orientation), that may also affect the steel’s strength properties, can be determined by the FMA, too.

In order to predict the effective properties of PMR-15/T650-35 composite ply in the temperature range [250-350°C], the time-dependent mechanical properties of PMR-15 matrix determined experimentally [1], were considered.
The mechanical properties of the fibers do not experience any change due to the aging process in such a temperature range [2, 3].
Consequently, the corresponding macroscopic thermal and hygroscopic properties will be affected, also.
The magnitude of the effective properties remains similar, however.
The macroscopic hygro-thermo-mechanical properties were evaluated numerically using the viscoelastic Eshelby-Kröner self-consistent scale transition model.

To explore machining properties of the EDM in gas basically, thermal fields of single pulse discharge in gas and liquid were analyzed by FEM software ANSYS.
While thermal properties of electrode material are assumed as all to the uniform, temperature distribution is symmetry to z-axis, and there is 0 T φ ∂ = ∂ .
Simulation with A SYS Typical mould steel Cr12MoV was selected as workpiece material, which properties is shown in Table 1[9].
Thermal strain graph can also be obtained by the FEM-program, which is helpful for analyzing organizational structure and understanding mechanical properties and residual stress of machined surface.
Guo: Thermal properties of engineering alloys (Metallurgical Industry Press, China 1994).

When selecting the pipeline repair technology, we mainly considerate four factors: whether excavat pipeline , whether cut off the water and the time of cutting off water , the time of pipeline repair , the materials of pipeline repair, and so on.
With comprehensive considerations of all kinds of important factors, taking it as an example to explore new joint repair technology strategy of water distribution network has the important practical and guiding significance [1].
The Factors Considerate When Choosing Repair Technology In the choice of water supply pipeline repair technology, the main considerations are that whether excavat pipeline , whether cut off the water and the time of cutting off water , the time of pipeline repair , the materials of pipeline repair, and so on.
Line installed technology lined with pipe slipping into, this technology insert a new plastic pipe into the old original pipe, grout in the annular clearance between the old and new pipeline for consolidation, form a type of tube structure with one pipeline in another, make pipeline both has the anticorrosion performance of the plastic pipe and the mechanical properties of the metal materials, and finally improve the work performance of the pipeline.
This technology belong to the unstructured line installation, is more suitable for repairing the cast iron pipe with good constitutive property [8].

Therefore, the mechanical properties of welded joints can be improved.
This software covers both the features of phase transformations, transformation plasticity, and phase respectively temperature dependent material properties.
The SYSWELD material database is used to model the material properties of the relevant phases.
The properties of the phases involved in the simulation are plotted as a function of temperature in Figures 2 and 3.
Fig. 2 and 3 depict the mechanical properties of selected base and weld metal phases.

Introduction Mine water inrush is one of the main factors which affects and threatens safety in the coal production, the disasters by mining over confined water make up about one half of all the mine water disasters, and safety that menaced by high pressure water is getting more worse in deep coal mine.
First, changes in pore pressure cause changes in effective stress, which affect the response of the solid, for example, a reduction in effective stress may induce plastic yield; Second, the fluid in a zone reacts to mechanical volume changes by a change in pore pressure.
The existing research results show that[2], the error caused by uncertain factors such as the width of fracture, distance of fracture and filling only affect on the values of main permeability tensor,can’t affect the direction of permeability tensor.
Fig.6 The contour of pore pressure when Fig.7 The contour of pore pressure when the workface was 150m apart from the fault the workface was 30m apart from the fault Conclusions (1)The permeability tensor of rock has important significance for researching permeability, and we can convert the permeability of discontinuous fractured rock mass to continuum anisotropic model by using it’s properties.
(3)The theory of coupling fluid-solid with FLAC3D can be used for numerical simulation of water inrush through coal seam floor nicely,the anisotropic permeability model can also simulate the floor rock the nonhomogeneous anisotropic permeability properties primely.

For ceramic materials, toughness and strength are two main factors that affect erosion resistance rather than hardness.
Table 1 Chemical composition of Cr15Mo3 in mass percent (%) Material C Mo Cr Si Mn P S Cr15Mo3 2.91 2.76 15.2 0.24 0.92 0.08 0.15 Table 2 Composition of the ceramic materials used in the experiments Material Composition Density (g/cm3) α-Al2O3 95% Al2O3 3.75 ZTA 80%Al2O3 + 20%ZrO2 4.08 Si3N4 84% Si3N4 +16% Y2O3 and Al2O3 3.40 Table 1.3 Mechanical properties of the ceramic materials used in the experiments Material Bending strength (MPa) Fracture toughness KIC (MPam0.5) Hardness HV2 (GPa) α-Al2O3 350 3 14.0 ZTA 600 5 14.5 Si3N4 850 7 16.0 (a) Cr15Mo3 (b) α-Al2O3 (c) ZTA (d) Si3N4 Fig. 1 Microscopic structures of Cr15Mo3, α-Al2O3, ZTA, Si3N4 Experimental equipment and parameters Experimental equipment adopted here is a rotary disk erosion wear tester with flowing suspensions of solid particles.
So the fracture toughness of ceramic materials should be thought as an important factor influencing the erosion resistance.
Compared to the hardness, the toughness and the strength are both main factor that affect the erosion resistance of ceramic materials.
Xi'an: College of Mechanical Engineering, Xi'an Jiaotong University, 2000.

In this paper, in order to evaluate the mechanical properties and reliability of structure, a systematic testing program is proposed, which includes the applied load, data acquisition, data processing.On the base of testing data, evaluating of the condition of the bridge through using comparative analysis method.
Analysis of Static Load Test Results The Efficiency of Static Load Test According to Bridge Engineering Testing Manual, the load efficiency factor should be between 0.95 and 1.05.
Therefore, the load test can reflect the construction stressing properties of the bridge which is under the city-A level car load.
And this structure is good in the mechanical properties and restoring elasticity ability.
Conclusion Through the bridge for testing, can be learned, operational status of the bridge to ensure its safe use, with the rapid development of China's transportation construction, a substantial increase in traffic volume, traffic density and vehicle load increases, these factors have led to a lower carrying capacity of the bridge, and even affect the safety of operations, Therefore, the comprehensive assessment of carrying capacity of the bridge is particularly important.

HSTRs could bear high temperature of 600-1200℃ and complex stress styles, and at this temperature keep good mechanical property for a long time.
Those factors above collectively caused that when tool passed the cutting area, chip broke away from woekpiece processing area immediately (Fig. 6).
Cutting temperature is a key factor that affects tool wear, tool life and workpiece surface texture, because both tool and workpiece materials weakened in high temperature.
There are plenty of factors affecting it, such as tool geometry, tool material, cutting data (cutting speed v, feed f and cutting depth aP) and so on.
Cutting force, heat and vibration were main factors.