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In this article the reaction design, thermodynamics, reaction mechanisms, reactive hot pressing or pressureless reactive sintering, microstructures and mechanical properties will be discussed.
(a) (b) Figure 7 Microstructure and properties of the Al2O3-BN composites.
(a) TEM micrograph of the Al2O3-13BN composite; (b) Mechanical properties.
The mechanical properties are shown in Fig. 7(b).
The micrograph and the mechanical properties are shown in Fig. 8.

The exact solution of complex function of the matrix and the renforcement layer are obtain in series form; then, the expressions of stress field, image force and stress intensity factor of crack tip can be derived; finally, numerical disccusions are pesented and the results shows that the lip-shaped crack in reinforcement layer has interference effect on the interaction of dislocation and reinforcement layer, and the eigenstrain in x-direction has little effect on image force; however, the eigenstrain in y-direction has great influence on image force.
Because of its importance on researching the strength and ductile of materials, it arouses much attention of many material and mechanical researchers.
The explicitly solutions of complex function are obtained in series for a screw dislocation located in reinforcement layer, and the expressions of image force and stress intensity factor are also deduced.
Finally, the numerical analysis is performed to discuss the influence of dislocation position, material parameters, the properties of reinforcement layer, etc. on image force.
(2) The eigenstrain in x-direction hardly affects the image force; however, the eigenstrain in y-direction can enhance the magnitude of image force in a great degree and can also change the sign of image force.

Thus, this paper summarizes an evaluation method of electronic process materials compatibility, which provides a reference for ensuring the quality of electronic process materials and improving the reliability of SMT products. 1 Typical Failure Modes of Electronic Components Caused by Solder Paste In the process of SMT reflow welding, there are many factors that affect the welding quality, including the design of solder pad, welding temperature curve, the quality of components and pins, quality and rationality of use of solder paste, printing quality of solder paste, etc.
The improper alloy composition will affect the surface tension and melting point of solder.
Corrosion failure of solder paste residue after welding is caused by many factors, mainly including alloy composition, flux composition and external environment [8].
The FT-IR spectra of the typical area of the failed product 2.2 Failure analysis of improper composition of trace elements Lead free solder is widely used because of its excellent wettability, mechanical properties and lower melting point.
Moreover, high mass fraction of phosphorus may also result in the segregation of Phosphorus at the surface, thus affecting the compactness of solder alloy surface film [12].

Al-Tabey* Department of Mechanical Engineering, Faculty of Engineering, Alexandria University, Alexandria (21544), Egypt Keywords: Neural network predication, Fatigue of composites, Expert systems, Neural network modeling Abstract.
A wide literature review showed that the fatigue behavior of composite materials is dependent on many factors.
Modeling of these factors effects involves the development of a mathematical tool derived from experimental data.
Three fatigue parameters (peak stress, minimum stress and probability of failure) as well as four mono- tonic mechanical properties (tensile strength, compression strength, tensile failure strain and tensile modulus) were selected as the ANN inputs, which were applied to predict the fatigue life of the composite as the output.
Serra [4] confirmed that the properties of the basic element (lamina) and their orientation within the laminate strongly affect the fatigue performance of composite laminates.

TRIZ Theory in the Application of Vacuum Circuit Breaker Improvement LI Shanmin1, a ZHANG Yu1, b ZHAO Xin2 GONG Shaocheng2 1Faculty of Mechanical and Electrical Engineering Kunming University of Science and Technology, Kun Ming 650093, China 2Yunnan Switch Electric Co., LTD, Chuxiong 675000, China aLism1986@sina.com, bzhangyu@public.km.yn.cn Keywords: TRIZ theory, vacuum circuit breaker, technical contradiction, heavy breakdown, contradictory matrix.
The surface of contact is one of the main factors of vacuum circuit breaker insulating properties, high frequency current will ablate the local surface of contact, making fusion welding when the contacts closed, and after the contacts opened, bumps will be produced in surface.
In the design process of vacuum arcing chamber, the surface contacts will always remain particles, more particles will be produced because of the role of vacuum arc, which directly affect the heavy breakdown process of vacuum gap [7]. 3 Solving the problem It can be seen that breakdown mechanism for vacuum gap shows vacuum contact's material and its surface condition are both the crucial factors for insulation of vacuum gap .Contact material has great impact to vacuum gap's voltage level.
When the materical strength is higher, welding force is greater and its anti-welding property is worse.
The problem of worse anti-welding property can be seen as a structure stability problem in general engineering parameters.

All kinds of impact could affect the minimum width of the narrow beam in WEDM [6].
A proper thickness of the beam is also an important factor to influence of the machining performance.
The material properties used for the input are listed in Table 2.
Table 2 Material properties Temperature (°C) 20 250 750 1500 Thermal conductivity (J/s m K) 50 47 27 35 Specific heat (J/Kg K) 460 480 675 660 Elastic modulus (Pa) 2.05e11 1.87e11 0.7e11 0.19e11 Yield strength (Pa) 2.2e8 1.75e 0.4e8 0.02e8 Finite element analysis results.Fig.6(c) shows the temperature distribution of the workpiece after the last discharge happens.
The influencing factors of the machining process such as single discharge energy, servo reference voltage and workpiece thickness are investigated.

It has also been show that sensory feedback is sufficient for entrainment of the neural controls to the mechanical resonance.
For our study, we will assume that , so that our structure is not affected by outside forces.
Note that Ti is calculated using a prestress factor P.
The nonlinearity ψ captures the saturation property of a neuron, and is assumed to be an odd, bounded, and strictly increasing function.
Brown, The Intrinsic Factors in the Act of Progression in the Mammal, Proceedings of the Royal Society of London.

Introduction Submersible motor is the power component of the submersible which performance affects the normal operation of the whole unit.
On the other hand used median filter especially point filtering technique in software design, which can response faster and smoother. 3 Data acquisition and processing of the dynamometer The test of motor includes the working characteristic of motor and mechanical properties.
Figure 4 shows the test interface. ① No-load test ② Locked rotor test ③Motor efficiency, power factor and slip test Fig.4 The test interface There are some parameters needed to be measured in the test process such as DC resistance, the copper loss, iron loss and mechanical loss at no-load test, locked rotor current and torque at locked-rotor test, the relationship curve of Pmi, I1, ηm, cosΦ, Sref and Pmu under the rated condition at load test.

Multiple studies have assessed mechanical properties of composite laminates.
In this paper, mechanical properties of GLARE laminates are tested through experimental methods, and its strength and tensile properties are studied.
The mechanical properties of 2024-T3 aluminum alloy and HS2 glass fiber prepreg are listed in Table 3 and Table 4, respectively.
Table 5 shows the mechanical property of the cohesive element.
The mechanical properties of material are used in table 3 through to table 5, and the size of laminates is the same as that in section 2.1.

Using waste to produce a new type of air entraining agent (AEA), carrying out research of the concrete’s mixture performance, mechanical properties and frost resistance durability after mixing with the AEA, with results showing that amount of air entrained in the concrete mixture and the water reducing rate increases along with the increase of the addition of the new AEA, and its compressive strength loss laws are similar with that of normal AEAs.
Introduction The durability of concrete has received common attention from people, and frost damage is one of the most important factors which affects the durability of concrete.
For the basic properties of the AEA see Table 2 and Table 3.
New AEA physical properties State Density Specific surface area Color Water solubility Fineness Powder 1.47g/cm3 2.891cm2/g Brown Micro merging with water 1.4 Table3.
Table 4 shows the air content testing mixture proportion of AEA added concrete mixture, and Table 5 shows the physical properties of AEA added concrete and frost resistance testing mixture proportion.