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Study on Bonding Properties of Copper and Aluminum in Nano Scale Using Molecular Dynamics Simulation Quang-Cherng Hsu1, a, Yen-Yu Cheng1,b and Bao-Hsin Liu 1,c 1Department of Mechanical Engineering, National Kaohsiung University of Applied Sciences 415 Chien-Kung Road, 80778 Kaohsiung City, Taiwan, R.O.C.
Introduction Though 7075 aluminum alloy (AA7075) possess good mechanical property, the thermal crack behavior will lead to bad welding strength.
Komanduri, etc. [1], analyzed single crystal material of aluminum, copper, Nickel with FCC and iron, chromium, tungsten with BCC, respectively, to explore the variation of mechanical properties during tensile test.
For example, properties of Ni and Pd, such as the lattice constant, elastic constants and sublimation energy are precisely derived by comparing to the experimental data.
In this study, bonding properties of three materials such as pure aluminum, pure copper and binary alloy (Al0.9Cu0.1) are analyzed.

Different inorganic fillers are used to alter the properties of neat polymer.
Those materials are known for their excellent thermal and chemical stabilities and mechanical properties.
The presence of functional groups on filler might generate a variety of interactions such as covalent, ionic, hydrogen bonding etc. with polymer matrix affecting the properties of composite.
The presence of functional groups on filler might generate a variety of interactions such as covalent, ionic, hydrogen bonding etc. with polymer matrix affecting the properties of composite.
The influence of POSS functionality on hybrid membrane’s thermo-mechanical properties, morphology, water uptake and proton conductivity was investigated.

The goals are to implement designs to fully mimic the properties of carbon nanotubes on larger scales for enhanced thermal and electrical management in addition to controlled strength and toughness.
The electrical properties of carbon nanotubes vary from those typical of semiconducting to those typical of metallic conductors depending on the type and chirality of the CNT.
The mechanical properties of carbon nanotubes are expected to equal of exceed the expected values of perfect materials.
The focus of this research is the application of robust carbon nanoparticles with superior thermal, electrical and mechanical properties and well established physical and chemical stability in order to design and manufacture new classes of very novel, unique and efficient carbon nanotube nanocomposites, with much lower additive concentrations.
With this model we can explore various factors that can affect thermal conductivity of nanofluids such as aspect ratio (L/D), decoupled orientation effects (along nanotube axis, Kl, transverse to nanotube Ktrans), along with overall volume loading.

Dynamic Analysis Methods of FLAC3D [6] There are two methods of dynamic analyses in FLAC3D, including nonlinear vibration analysis and equivalent linear vibration analysis, considering the mechanical properties of structural materials and large deformation.
Nonlinear dynamic analysis is to build the model considering the nonlinearity in space and time of the physical and mechanical properties of materials, and the different stages of deformation and failure on the model elements adopt different damping ratio and shear modulus to calculate the dynamic responses.
Calculation Steps Dynamic analysis is generally divided into the following two steps: the first step is static equilibrium calculation under a certain geological conditions including model range, initial conditions, material types, constitutive model as well as filling, excavation and lining of model; the second step is dynamic response analysis after applying dynamic load involving dynamic boundary, mechanical damping, properties of dynamic load as well as propagation properties of load in medium etc.
A safety factor of 0.5 is used, because formula is only an estimate of the critical time step.
Analysis of the affecting factors for seismic response of immersed tunnel[J].

Cracking of concrete structures is one of the important factors that affect durability and functionality.
Cracking Description and the Crack Mechanical Analysis Cracking Description.
To quickly determine the cause of the cracking, we conducted the analysis of these factors with exclusion method.
Table 2 Concrete mixture and properties of pier Part Grade of concrete Theory admixture Cement Fine aggregate Coarse aggregate additive water pier C20 1 2.12 2.92 0.01 0.59 Bearing tray C25 1 1.83 2.74 0.01 0.52 Part Grade of concrete Construction admixture amount per cubic (kg) Cement Fine aggregate Coarse aggregate additive water pier C20 356 754 1041 3.56 210 Bearing tray C25 394 720 1081 3.94 205 The piles were poured with two round-ended steel formworks and 1.8cm thick bamboo plywood in the middle section.
Reinforcing method Because the bridge pier is C20 grade plain concrete structure as a compression member, the crack depth does not exceed half of the pier thickness, generally the cracks do not have much impact on the structure mechanical performance, does not affect services.

Mechanical Reliability of a Segmented Silicon Layer on Ultra-thin Polyimide Substrates L.
The mechanical properties such as crack, interfacial delamination are critical to reach the flexible substrate.
It is necessary to explore the interface properties in order to improve the quality of flexible ultra thin substrate.
In this contribution, the special setup is designed to measure interface strength of the ultra thin film combining by Finite element calculation with the consideration of mixed mode, temperature, humility and other factors.
The development of the first cracks depends significantly on the silicon layer segmentation size, which affects both the crack density and the crack width.

During the process of multiresolution analysis of the signals, the wavelet coefficients of the useful signals and the wavelet coefficients of the noises have different properties on different scales, which are used to distinguish the useful signals and noises.
The result of the wavelet threshold denoising method is mainly related with the following three factors: the number of the decomposition scales, the choice of the wavelet function and the choice of the threshold function.
The denoising result is affected by the number of the decomposition scales greatly.
The denoising result is affected by the choice of the wavelet function greatly to some extent.
After analyzed the three affecting factors, the factors of wavelet threshold denoised method are confirmed.

In order to find out the influence trend and the impact factor of different process parameters for die-roll of gear shape and smooth-shear surface, the forming process to characteristics of FPG fine-blanking that based on fine-blanking theory was simulated by using Deform-3D.
The material thickness is 4.0mm, the mechanical properties is shown in Table 2.
Fig. 1 Seat adjusting mechanism Table 1 The geometric parameters of gear Modulus[mm] Tooth number Pressure Angle [°] Tooth high [mm] 2.25 31 0 3.8 Table 2 SAE1020 mechanical properties Tensile strength [Mpa] Yield strength [MPa] Elongation[%] Hardness[HB] 440 346 35.8 116 The finite element simulation took Deform - 3D model and the blank was meshed for 50000 units.
Following the constant volume condition, the material formed by punch should be ideally equal to the material filled with the cavity in order to ensure the integrity shape of gear, otherwise forming performance would be affected.
Compressive load increased as the friction factor increased.

A proper balance of these two opposite conditions requires a good control of all the main factors intervening in both machinability and ductility properties.
In addition, reheating conditions prior to hot rolling will affect this surface, eliminating but also promoting new defects or “weak regions”.
During hot rolling operations, this surface region will be affected by a stress state that can differ from the bulk region.
In this type of mechanical tests the surface of the specimens is smooth without initial defects and, in consequence, nucleation of defects takes an important part of the total applied strain.
Fig. 9 Example of inclusions with voids in conditions corresponding to dynamic recrystallization (steel 9SMn28, T = 1150ºC, 1 s-1, e =1.9) Concluding Remarks The hot workability problems of resulfurized steels are related to a combination of factors where the characteristics of the region close to the billet surface, as well as the high fraction of MnS particles, play a central role.

For many recycled plastics, materials with different rheological properties and melting points are usually mixed together, and can not be separated.
Finite element simulation is calculated to analyze the relationship between operation factors of pelleting process and blocking situation of die holes.
Because recycled plastics usually contain many different materials, and different materials have different rheological properties and melting points[7-8].
In this work, based on finite element simulation for extrusion situation of die-plate, the factors which have an important affect on die-hole blocking are studied.
For recycled plastics, materials with different rheological properties and melting points are usually mixed together, and can not be separated.