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As the thin film layers have very different mechanical and material properties, traditional machining processes, such as grinding, often lead to delamination at layer interfaces [6].
The successful understanding of the delamination mechanisms for multilayered structures relies on not only the mechanical properties of individual film material, but also the stress concentration induced by the mismatch of materials properties at the interfaces.
The mismatch of material properties between two layers, i.e.
Summary For a multilayered thin film structure, both tensile stress and shear stress at interface is crucial factors in delamination mechanism.
The stress at the interface is caused by the mismatch in the plastic properties of the two neighboring layers.

Put the materials in the oven with the temperature of 70°C for 168 hours and test the change of mass and corresponding mechanical properties. 4.
Perform fatigue tests for the materials with the 1040 cycles and test the change of corresponding mechanical properties. 2.3 Analysis of experimental results The original mechanical properties of the four coating fabrics are shown in Table 1.
Table 3 showed the change of mechanical properties of polyurethane coated fabrics after oil immersion.
Table 4 showed the change of mechanical properties of polyurethane coated fabrics after thermal ageing.
On the contrary, the mechanical properties of polyurethane coated fabrics are much better than those of glass fiber cloth coated with silica gel.

The Effect of Two-Step Aging on the Electrical Properties of 7075 Aluminum Alloy Jianhua Zhong1, a,Yinping Xiao1,b, Hongbin Zhu1,cand Kai Feng1,d 1Jiangxi University of Science of Technology, Materials and Chemical Engineering,Gan Zhou Jiangxi ,341000,China azq8613@163.com, bxyp063@126.com, c2dong321@2008.sina.com dfegnkai02@126.com Keywords: 7075 Aluminum Alloy; Extrusion; Electrical Conductivity; Two-Step Aging Abstract: This experiment has taken a research on the conductivity changes of 7075 aluminum alloy after being extruded and two-step aging treatment,and has done a analysis on the theory and rules of the impact on conductivity performance under the two-step aging treatment.Compared to cast aluminum alloy and extruded aluminum alloy without two-step aging process,the experiment showed that extruded alloy with two-step aging treatment has the highest conductivity about 44% IACS, 33.3% more than under casting condition and 22.2% more than only being extruded.
Discussion 7075 aluminum alloy will undergo a series of physical and chemical reactions during condensation process which resulted in irregularity inside the alloy.Alloy contains shrinkage,cracks,air bubble, dendrite of different size and shape and locations,as well as crystal segregation and zone segregation,etc.[4].These defects have caused more dispersion during conducting of electrons.Then air bubble and crakes also decreased the effective area of electron transmission.So all these factors have affect the resistance which lead to low conductivity of the materials.
[7] Chen Xiaoming, Song Renguo,He Yuan , Zhao Jian and Li Hongxia.Effects of Double-Peak Aging on Microstructure and Properties of 7075 Alloy,Aerospace Materials &Technology,2009, 39,(6):23-25 .
[8] Zhang Shixing,Wu Haihong, Deng Penhui and Lu Ying.Influence of Heat Treatment Process-on Microstructure and Mechanical Properties of 7075 Aluminum Alloy.Hot working Technology, 2008,37 (22):56-58.

For example, Wiebenga, Atzema, An, Vegter and van den Boogard [17] examine the variation in the mechanical properties of 41 coils.
To date, most of the simulative studies concerning the influence of various parameters on the part quality indicate that the significance of individual factors vary depending on the part, part region and the state of other factors.
Previous variant simulations in sheet metal forming operate with dramatically reduced and simplified factors.
Steel manufacturers apply this method in the field to measure mechanical properties of running strips [24].
An explicit examination of the parts’ mechanical properties is not given, although a defect might have an effect on assembly.

Within the research the influence of partial substitution of wood with glass fibres on board properties was monitored.
It is used mainly due to economic reasons, because it is cheaper than cement, it shows hydraulic properties and thus supports the board strength.
This phenomenon can be explained by several factors.
The different properties of glass fibres and wooden chips can be considered as the main reason.
This paper was also elaborated with the financial support from the budget under the project FAST-S-14-2318 „Study of the microstructure and physical-mechanical properties of cement composites with organic filler”.

Introduction The shear modulus and damping ratio are two mayor index of dynamic properties.
Since the factors which affect soil dynamics parameters are as many as 13 to 15[1], the soil around the kinetic parameters are quite different, and special test measurement are generally required in major projects.
Dynamic parameters of rock and soil are not constant, which are not only related to its strain amplitude, but also related to frequency of vibration loads confining pressure, density, plasticity index, loading history, saturation and other factors.
We can see that the effective stress is an important factor which affects the sample’s resonance frequency.
Hardin and Black pointed in 1968 that the shear modulus was affected by serious of factors which can be expressed as: (3) Where:is the average effective principal stress, is frequency, is void ratio, is particle characteristics, is shear strain amplitude, is mass structure, is time effect of secondary consolidation, is hexahedral shear stress, is loading history, is saturability, is temperature.

The output characteristics of HEFT is shown to respond very sensitively to changes in the electrostatic boundary conditions caused by the adsorption of ions, wetting by polar liquids, exposure to gases, or the piezoelectric polarisation due to mechanical strain.
Thus, it is necessary to research the properties of AlGaN/GaN HEFT-micro- cantilever accelerometer at various temperatures for exploring the potential of GaN/AlGaN HEFT at high temperature and showing the temperature-dependence on I-V characteristic and piezoresistive coefficient.
The carrier transport mobility rate affect current both in liner working area and saturated working area.
The primary factor to affect carrier transport mobility rate is several of scattering mechanism.
But the mobility μ play an important part to affect IDS and IDDS.

Their mechanical and tribological properties were compared in terms of their application in the field of surface engineering.
However, both coatings provide adequate strength properties for the substrate.
The correct structure of the deposited coatings has a real impact on the mechanical properties of the elements covered with it.
The structure analysis carried out to indicate the relationship between mechanical properties and the cathodes used in the coating process.
Petkov, Influence of thermal treatment on the mechanical properties of TiAlSiN-based coatings, Journal of Chemical Technology and Metallurgy 48 (2013) 567–570

FEM Analysis of Contact for Converter Spherical Hinge Xue Ping Ren1, a, Jian Da Gao2,b 1 Department of Mechanical Engineering Inner Mongolia University of Science & Technology Baotou, China 2 Department of Mechanical Engineering Inner Mongolia University of Science & Technology Baotou, China arxp@imust.cn, b gaojd_1986@163.com Keywords: Converter；Spherical hinge support；FEM Abstract: The role of converter spherical hinge is one of the main components, combined with practical work and With help of FEM, Thermal Stress coupling field of spherical washer can been obtained through numerical simulation.
Introduction In process of converter working , at the contact surface of the spherical pad and a lower spherical seat is not only affected by the loading but also by the action of high temperature released by the furnace body, physical property parameters of connecting device material changes with temperature, the spherical hinge in a very complex and harsh working environment ,at the same time in the process of the work, the spherical pad relative to the lower spherical seat relative sliding, resulting in the contact area decreases, sometimes resulting in contact stress is too large in the special position, the force will be transferred to the bolts, the bolt tensile stress increases will make it easy to fracture.
Friction stress The maximum stress for ，Contact friction stress 340，( The safety factor 1.5) Although theoretically is safe, but the safety coefficient is low.
Oxygen converter steelmaking [M] Mechanical Industry Press,1983.3 [2] Pu Liang gui,Ji Ming gang.
Mechanical design [M].

This version of the approach allows assessment of fatigue properties of the detail without utilizing Neuber’s formula and presenting the loading history in the block-type format.
In the high-stress range of the service loading the input of this over-estimation of fatigue damage in the total sum typically is insignificant due to stochastic properties of excitation.
(2) Criterion (Eq. 2), as well as (Eq. 1), provides conservative evaluation of fatigue properties of a structure, since it underestimates the fatigue lives approximately, in the range of cycles, as indicated Manson in discussion of [3].
The stress in the flange at the cut ending is magnified by the cut shape; respective stress concentration factors must be calculated by the finite-element method.
Peterson, Stress Concentration Factors, A Handbook, J.Wiley & Sons, Hoboken, NJ, USA (1989)