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Introduction Erosion is a complex process affected by many influencing factors and it has long been recognized as a potential source of problems in oil and gas production systems.
Material properties.
Material properties have a significant effect on erosion.
Steels and other metals generally show ductile erosive properties [5-7].
Important factors determining the particulate erosion rate are: the sand flow rate, the physical properties of the fluid (density, viscosity, temperature, et al) and the size, shape and hardness of the particles.

The properties include excellent mechanical properties and good permeability.
Table 1 shows the physical properties of all the Kenaf nonwovens samples.
Overall, there are two factors that influence the result comparison of this research.
Mukhopadyay, Bulk and Physical Properties of Needle-Punched Nonwoven Fabrics, Indian J.
Factors Influencing Acoustic Performance of Sound Absorptive Materials, Aust.

From the results, tensile properties and hardness of TPVs are slightly affected by processing conditions.
Parameters of mixing and products’ properties will be studied.
Physical Properties Table 1 shows physical properties of TPVs.
However, we found that the mixing pattern has slight effects on mechanical properties of TPVs.
Soares, The Effect of Mercapto- and Thioacetate-Modified EPDM on The Curing Parameters and Mechanical Properties of Natural Rubber/EPDM blends, Eur.

Therefore, microscopic models of asphalt mixture can include most of the important factors that govern the performance of asphalt mixture.
Damage and anisotropy are important micro-structural factors that influence the macroscopic behavior of granular materials (e.g.
To account for these two factors, it was necessary to multiply the measured binder stiffness by a factor to obtain the stiffness of the mastic.
Dai [4] presented 2D and 3D micromechanical finite element (FE) models to predict the viscoelastic properties.
Micromechanical analysis of viscoelastic properties of asphalt concretes.

The key factors of synthesis experiment involving the carbon source, the catalyst and high temperature heat source.
Compared with metal materials, carbon fiber has the characteristics of high strength, high modulus, low density and low coefficient of linear expansion on the physical properties.
Although carbon nanofiber is a new member in the family of carbon materials, it has the excellent properties and has wide application prospects.
But the analysis of main affecting factors can reveal the formation and growth mechanism of carbon nanofiber in the flame.
The key factors of synthesis experiment for carbon nanofibers involving the carbon source, the catalyst and high temperature heat source.

Introduction Wear and corrosion is an important failure form among mechanical parts.
During the usage process, working equipment or transmission system of machinery equipment could become invalid unavoidably due to the quality of material processing and assembly, climate and work environment, quality of fuel and lubricating materials, operation and other factors[1-4].
These changes will damage the formal superficial size and property of the surface of mechanical parts, which deterioriate technology gradually and lead to mechanical accident in the worst.
Smaller heat affected zone.
High hardness, high wear resistance, high bonding strength, suitable for steel, iron, copper, aluminum and other metal materials, can solve the high wear, corrosion, scratches, cracks, surface failure of precision repair, edges and corners, interior angles defect repair, and repair the surface of special shaped puzzle that can strengthen the surface properties of components to extend the service life of components in the broad field of surface engineering applications.

A Study on the Fretting Wear Resistance of a Zirconium Alloy with the Variation of Supporting Spring Properties Young-Ho Leea and Hyung-Kyu Kim b Korea Atomic Energy Research Institute 150 Dukjin-dong, Yuseong-gu, Daejeon, 305-353, Republic of Korea a leeyh@kaeri.re.kr, bhkkim1@kaeri.re.kr Keywords: Fretting wear, Zirconium alloy, spring shape, slip amplitude, mechanism, spacer grid, nuclear fuel rod.
From the experimental results, the fretting wear mechanisms and the effect of spring properties were discussed.
This is because its mechanism is quite complex and the many variables affecting the fretting wear phenomenon has a mutual relationship with each other.
However, this causes a change of the mechanical properties that affects the fretting wear behavior.
An accumulation of wear particles in the dry condition has beneficial effects on the wear properties due to the formation of a load-bearing layer [5] while the wear debris is rapidly removed from the contact surfaces in concurrence with it's generation under a water lubrication.

These micro parts may be produced by Micro electro-mechanical system (MEMS) technology.
Alternatively, metal forming is one of potential technologies especially suitable for the mass production of metallic parts because of the advantages of high production rate, minimized material loss, excellent mechanical properties of the final product and close tolerances.
The factors used to investigate the size effects include the size of grain and the size of feature.
The above literature reviews show that grain size does affect material flow behavior.
The above results show that grain size affects the depth of the deformed dome.

Study on Calculation Theory of Elastic Flexural-torsional Buckling Bearing Capacity for Castellated Beams Xiangrong Chen 1, a, Hailong Yuan 1,b, Xing Chen1,c, Zhenwen Liu1,d 1 School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China email: acxr90@126.com, byzl8801@126.com, ccx0411@sina.com, dhippohappy@163.com Keywords: castellated beams; elastic flexural-torsional buckling; calculation theory; influence factors Abstract: The structure of castellated beams is complex, using the computation theory of elastic flexural-torsional buckling of H-shaped beams to study the elastic flexural-torsional buckling strength of castellated beams under different loads, based on simplifying the section's eigenvalues.
Introduction Castellated beams are made by cutting the I beams or H-shaped beams along the dog-leg path on the web and rejoining the two halves by welding, which are widely used in practical engineering as the superior mechanical properties and yield good economic returns.
Analysis of influence factors on the elastic flexural-torsional buckling of castellated beams 5 castellated beams were designed and analyzed by the ABAQUS software to text the effects that divergence ratio had on the elastic flexural-torsional buckling critical load, keeping span and distance- height ratio as fixed constants, just chang the divergence ratio.
13.126 133.459 2 1.4 420 200 8400 0.35 63.380 13.414 133.702 3 1.5 450 200 8400 0.35 64.853 13.728 142.082 4 1.6 480 200 8400 0.35 66.481 14.074 146.836 5 1.7 510 200 8400 0.35 68.114 14.418 151.368 It can be seen from Table 3,4 that the influence of distance-height ratio on the elastic flexural- torsional buckling bearing capacity of castellated beams is small, as the increment of distance-height ratio the change of the bearing capacity is less, however ,the influence that depth-span ratio dose is great, with the decrease of depthspan ratio the bearing capacity declines linearly, the divergence ratio also affects
Conclusions Conclusions are drawn from the research of calculation theory and finite element analysis： (1)The reduced calculation methods for section eigenvalues of castellated beams are of high accuracy and the calculation formulas are simple, which can be used to any hexagonal castellated beams, avoiding the computational difficulty brought by the complex structure.(2)After the simplified calculation for eigenvalues of castellated beams, the computation formulas of elastic flexural- torsional buckling bearing capacity for plain girders can be used to calculate the bearing capacity of castellated beams, which are simple and of high accuracy.(3)Through the analysis of affecting factors, it is concluded that depth-span ratio impacts the elastic flexural-torsional buckling bearing capacity of castellated beams greatly, the influence of divergence ratio is not obvious, the effect of distance- height ratio can be ignored.When designing, we should choose larger divergence ratio to increase

Comprehensively considering the lateral force, axial force, bending moment and other factors of the spring section, .
Then define the spring material according to the physical and chemical properties of the given 17/7PH steels under the status of ASTM A313-631 CH-900, and load it in the finite element model.
According to the characteristics of the spring and its shear stress, the regression model consisted of the third-order polynomial expression should be able to reflect the regression properties of the maximum shear stress.
Figure 3 The predictive error interval when the confidence is 99% (the model with the maximum shear stress) It has been observed from this model that the most active factor affecting the inner stress of the spring is the spring wire diameter, while the pitch plays only a small role in the shear stress of the spring.
Wahl, “Mechanical Springs 2nd Edition”.