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Temperature and Stress Dependence of Mobility of Screw Dislocation in BCC Iron Hideki Mori1,a 1Department of Mechanical Engineering, College of Industrial Technology, 1-27-1 Nishikoya, Amagasaki, Hyogo 661-0047, Japan amorih@cit.sangitan.ac.jp Keywords: Bcc iron, screw dislocation, Peierls stress Peierls barrier, free energy gradient.
Introduction Dislocation motion plays a important role in the mechanical behavior of bulk metals, and the Peierls stress and barrier are critical factors in determining the dislocation motion [1,2].
The size of the dislocation core is typically ten to several tens of atomic spacings, and thus the Peierls stress and barrier are intrinsically affected by the discrete atomic nature.
The dislocation migration is affected by the atomic configuration both in and around the dislocation core because of the stress field of the dislocation.
This temperature dependence may affect the mechanical properties of bcc iron.

Modal identification techniques are used to estimate the dynamic properties of a structure based on experimental data.
The mechanical properties of the pultruded profiles employed are listed in Table 1.
Mechanical properties of the PFRPs profiles, experimental data Mechanical properties Symbol Value Longitudinal tensile strength σz 350 MPa Transversal tensile strength σx = σy 70 MPa Longitudinal elastic modulus Ez 24.4 GPa Transversal elastic modulus Ex = Ey 9 GPa Shear modulus Gxy 3.6 GPa Shear modulus Gzx = Gzy 3.2 GPa Poisson’s ratio νzx = νzy 0.23 Poisson’s ratio νxy 0.09 Density γ 1850 kg/m3 Fibres percentage Vf 48% Finite Element Analysis (FEA) In order to choose the most correct settings and procedure for dynamic identification, a preliminary modal analysis was run on the whole structure by means of the calculation code Strand7.
Russo, Free vibration of pultruded FRP elements: Mechanical characterization, analysis and applications, J.
Russo, On mechanical performance of different type of FRP beams as reinforcement of pedestrian bridge.

Low Energy High Current Pulsed Electron Beam (LEHCPEB) Treatment: an Effective Way for Improving Surface Microstructure and Properties T.
This is particularly true for tribological [2,4] and corrosion properties [5-7].
The surface properties revealed in Fig. 1 must be determined by the final structure-phase states generated by the LEHCPEB thermo-mechanical treatment.
The more advanced dissolution process of the carbides [16], together with the ultra fine grain size of the matrix grains [14, 19] are considered to be important factors for the stabilization of the γ phase.
This layer can improve drastically the corrosion properties.

The Nanomaterials exposure pathway is also an important factor.
In such a small scale, the classical theory is no longer applicable, quantum effects (quantum effect) have become a factor cannot be ignored.
Coupled with significant increase in the proportion on the surface area of the material showing the physical, chemical and biological properties different from the macroscopic scale.
Nano exterior paint mainly uses the of nanomaterials binary synergistic the lotus leaf mechanism, the use of very low surface tension, adhesion ability and high hardness and toughness, aimed at strengthening the external walls of self-cleaning, anti-dust anti-dirt adhesion, UV resistance and gloss retention and color retention and other properties.
Textiles are capable of storing energy while retaining the mechanical properties of the fabric.

Introduction Torsion testing is an important experimental method to test the mechanical properties of a certain material.
The most commonly used torsion testing machine usually measures mechanical properties of materials in the big torque conditions, which can not accurately test the torsion properties of mechanical structures in the micro-torque / deformation conditions of service or the small size structure.
In order to improve the accuracy of the test, a small-scale torque sensor used to test the mechanical properties of biological bone issue has been designed.
Structure of the Low-range Torque Sensor The torque sensor is designed for the test of the mechanical properties of biological bone issue in this paper and the range of it is typically 0 to 0.5mN•m.
However, stress gradient is large which causes it difficult to paste the strain gauge and affect the accuracy of measurement.

Their physical and chemical properties were analyzed.
Introduction Enameling of metals is a widespread method of protecting metal products from corrosion and giving them certain technical and operational properties.
For enameled products, especially for household purposes, not only physical, mechanical and chemical, but also aesthetic-consumer properties are extremely important. [1] In the market of consumer goods, the most popular products are those with white coating.
Thus, analyzing the compositions of synthesized enamels and their aesthetic-consumer properties, it can be concluded that white coatings with a yellow hue have a greater diffuse reflection coefficient than with a blue hue, and these optical properties are affected not by the presence of coloring impurity compounds and the presence of rutile or anatase form of titanium dioxide, but the nature and intensity of the TiO2 crystallization process.
Enamelling of metal products, Mechanical Engineering, 1972

One of the most important factors for producing nanofibers using solution electrospinning is their concentration.
As mentioned above, factors that affect electrospinning process are varied, such as the surface charge, the injection pressure, the collect distance, the flow rate and the nozzle diameter.
Size, shape and collection methods may provide a potential approach to produce fibers with new properties.
Wei, One-dimensional conducting polymer nanocomposites: Synthesis, properties and applications, Prog.
Morphological control of electrospun jets and the fiber structures & properties.

These factors must be integrated consideration during design[1].
Speaking from the most extensive meaning, the finite element model including node, unit, material properties, real constant, boundary conditions and some other characteristic parameters reflect the physical structure of frame system.
Fig.1 The CAD model of the agricultural tricycle The frame mainly adopts 16 Mn alloy steel and Q235 steel, alloy steel was used in the beam and rail of the main parts, the steel of other parts adopts Q235 steel, the mechanical characteristics of these two steel was shown in Tabel 1.
The mechanical characteristics of the tricycle frame The outer profile of frame 3415×1260×1500 The complete vehicle mass 125 kg The maximum payload 350kg Maximum speed 80km/h Maximum total mass 4800 kg Grade ability ≥10° Frame type (pipe, plate, pipe) Pedal tube type Shell63 element type was established in the Nastran, and simplified the model without affecting the accuracy of model.
The division of the element grid and the size of the element directly affect the precision of the calculation in finite element analysis.

The purpose is to study the synergetic effects of such parameters on the contact stress non-uniformity (NU), which directly affects the spatial non-uniformity of the material removal rate on the wafer surface.
One of the most important factors causing NU is the phenomenon of stress concentration on the wafer edge.
Meanwhile, for a multi-zone wafer-back pressure profile to affect the contact stress distribution on the wafer surface, the wafer deformation has to be taken into account.
The mechanical and surface properties of the pad and wafer are listed in Table 1.
Note also that, as the retaining ring is assumed to be rigid in the present model, its mechanical properties are immaterial.

The epoxy resin packaging material is made up of epoxy resin, filler and curing agent, and can provide mechanical support and insulating property for the integrated circuit board.
Besides, the filler will affect crystallinity and crystallite size of the polymer so as to change its thermal conductivity.
Based on the above analysis, filler was supposed to distribute evenly in the resin, and the mathematical expression is as follows: Lgλ = VC2 lgλ2 + (1-V) lg (λ1C1 ) (2) C1 - influence factors of crystallinity and crystallite size of polymer, C2 - free factor of formation of heat conductive chain.
The relative factors have been calculated and processed by equation (3), as shown in Table 1.
The preparation and properties of epoxy molding compounds filled with multiple ceramic particles.