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In this study, the effects of friction on tensile properties, microstructure and strain distribution of commercially pure Al sheets were investigated using experimental and numerical methods.
Introduction Ultra-fine grained (UFG) materials obtained through severe plastic deformation (SPD) are of great importance due to their unique mechanical and physical properties [1].
Since originally proposed by Shin et al. in 2002, CGP has been successfully used for grain refinement and mechanical property improvement of various sheet metals and alloys [2-5].
Results and discussion Tensile properties.
Fig. 1 shows the variation of tensile properties of pure Al with CGP pass.

Table 2 Mechanical properties of fabrics hydroentangled nonwoves Items Hydroentangled nonwoven fabrics Normal PET fiber Hydrophilic PET fiber MD Tensile stength(N) 101.39 559.63 CD Tensile stength(N) 26.51 181.46 Entanglement coefficient(EC) 1.12 7.16 It can be seen that both MD and CD tensile strength of the high strength hydrophilic PET hydroentangled nonwoven fabrics are significantly higher than normal PET hydroentangled nonwoven fabrics from Table 2.It is said that the tensile strength of the hydroentangled nonwoven fabrics positively correlates with the hydroentanglement intensity.
Fig.3 Percentage of broken fiber and average pull-out force Cohesive force of fibers in the pre-webs The authors did some research on the fiber tensile strength, crimp, hydrophilicity of fiber surface and friction properties in order to find influence rule between the fiber properties and spunlaced nonwovens performance but there is no ideal results [1].
In this paper further uses the fiber cohesion index to study the influence factor of fiber entanglement.
Some researches about fiber cohesion on the quality of yarn forming have found that cohesive force of fibers is affected by the fiber crimp, fiber length, fiber linear density, friction and surface properties which are influencing factors about the fiber entanglement during spunlacing process [8].
The Influences of Hydrophilic Finishing of PET Fibers on the Properties of Hydroentangled Nonwoven Fabrics [J].Journal of Engineered Fibers and Fabrics, 2010, 5(4):26-32 [2] P.

Both static and dynamic tests were carried out at the aim of evaluating the residual load-bearing capacity and investigating the effects of deterioration on their dynamic properties.
Several factors, as aggressive environmental conditions, corrosion and cracking propagation due to cyclic loads, may bring to a substantial reduction of the safety margins.
Indeed, the edge beams usually undergo higher stress levels and are more exposed to deterioration factors, as weather, chemical attacks of chlorides contained in de-icing salts and pollutants emitted by vehicle traffic.
Each deck of the viaduct was built by five beams having the geometrical and mechanical characteristics nominally equal.
Both the scaling factors have been estimated through a FE model, assuming the mean values of the material properties and the geometrical dimensions reported in the original design documents.

Very often, these properties are difficult to be obtained from single FRP composite and conventional materials.
According to Benardos et.al. [4], surface roughness of drilled FRP composite was influenced by cutting tool properties (tool material and geometry), machining parameters (feed rate and cutting speed), workpiece properties (hardness, lay up sequence) and cutting phenomena (vibration and lubricant).
Their study showed that feed rate and spindle speed are the key factors affecting the surface roughness of drilled parts.
Nevertheless, the interaction factors were found to be insignificant.
From this, it is statistically proved that feed rate is the major factor affecting surface roughness in drilling CGCG hybrid composite followed by tool geometry and spindle speed.

Chemical vapor deposited (CVD) diamond film has a series of outstanding properties.
Introduction The outstanding properties of Chemical vapor deposited (CVD) diamond film, extreme hardness, low friction coefficient, excellent wear resistance and high thermal conductivity address CVD diamond film as the ideal cutting and drilling tools [1-3].
Before the temperature field analysis, follows are some assumptions made to simplify the calculation: The physical properties of CVD diamond film (such as thermal conductivity, heat capacity and density) are isotropic and symmetrical.
With the above-mentioned assumptions and the mathematical model for heat transfer and mechanical properties mentioned in Refs [10], a thermal analysis is performed to calculate the temperature distribution in the workpiece by using ANSYS.
Optimal scanning speed and laser power The power of the laser and the scanning speed are two key factors in the machining process of CVD diamond film.

To research the effect of the material factors with varying speed and pressure conditions, Kumar et al. used a tribological testing rig to evaluate braking performance.
The relative contact pressure p, relative sliding velocity v, and interface relative contact temperature θ are considered to be the influencing factors that need to be corrected, and the correction equation can be obtained: (4) where, K=K0/Ka is the relative wear coefficient.
(a) Braking speed 800 r/min (b) Braking speed 1000 r/min (c) Braking speed 1200 r/min (d) Wear curves Figure 7 Wear results of brake disc with different initial braking speeds. 4.4 Effect of friction coefficient on disc surface wear The working environment of the friction interface is not only affected by complex and variable external factors but also affected by the working life of the brake disc surface [11].
A study on mechanical and tribological behavior of brake pad materials, J.
Tribological properties of aluminum-clay composites for brake disc rotor applications, J.

Therefore, this article introduces the girder method, based on test results, it is very effective method that load-carrying capability is analyzed using the finite element software ANSYS by establishing mechanical models.
BEAM44 beam unit was utilized for the finite element models of whole structure, tried to reflect physical properties of structure, mass distribution, and condition of constraints and so on.
Crossing section was divided four parts including virtual longitudinally girder, the left side rib, the right side rib, right virtual longitudinally girder, the cutting of virtual crossing girder turned over several factors, such as constraint condition change, crossing section change, pivotal cross section and the correspond of longitudinal and crossing girder span and so on, as well as, every stiffness parameters of element were calculated in accordance with the actual width.
Summary The Method of grillage is a kind of method for simulating spatial analysis of wide, the simplified mechanical model could give expression to the mechanical characteristics of true bridge structure accurately to some extent, the result of a calculation are in accord with the results of loading test.
During the finite element modeling of the bridge, the factors affecting the accuracy of the finite element model are discussed in detail, as can be seen from the data analysis that loading states of model 1 is close to fact, so this method of breaking in the paper can provide the guidance for analysis on structural behavior of the prestressed concrete box girders construction of the kind.

A new structure of mechanical pulse CVT –rotational swash plate pulse CVT was put forward.
Introduction Pulse continuously variable transmission is a type of mechanical transmission.
But the gear module determines the gear tooth root bending fatigue strength, so it affects the transmission dynamic performance.
Zhou: Mechanical Continuous Variable Transmission (China Machine Press, China 2001) [3] Y.Q Zhou, X.L.
Dong: Journal of Mechanical Transmission, Vol.29(2005)No.1, pp.65-68.

Semi-solid processed components are heat-treatable and weldable and show superior mechanical properties.
An important element affecting the rheology in SSM processing is related to the particular microstructure of the alloy used and to its thixotropic behaviour.
Wang; Microstructure and mechanical properties of rheo-diecast AZ91D magnesium alloy; J.
Pan; Effects of rheocasting and heat treatment on microstructure and mechanical properties of A356 alloy; Scripta Materialia 53 (2005) pp.201–6
Zheng; Microstructure and mechanical properties of A356 aluminum alloy wheels prepared by thixo-forging combined with a low superheat casting process; Trans.

Introduction The relative displacement between the connection parts of the shafts, including the axial displacement, lateral displacement and angular displacement, is caused by the various factors during the process of the machine installation and operation.
Here the mechanical model of this kind of coupling is produced basing on the diaphragm shown in Fig. 3.
Fig.3 Schematic diagram of four bols flexible Fig.5 Change of angle displacement membrane a) Misalignment angle b)Lateral misalignment c) Axial displacement d）General form Fig.4 Shaft misalignment 2.3 Diaphragm stress analysis Diaphragm materials is 40CrNi2MoA, mechanical properties is σb=1960MPa, σs=1605MPa, [σ]=802MPa, μ=0.3, E=200GPa, ρ=7900kg/m3 and safety factor is n = 2.
This explains that the mechanical model and the assumption used by the theoretical analysis is appropriate
Diaphragm Stress and Effective Factor Analysis of the Flexible Laminated Membrane Coupling.