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Further more, the heat-release problem is also one of the key factors.
Packaging Materials Packaging (materials, technology, etc.) is also one of the key factors that affect the luminous efficiency.
Electric silver paste is a composite material adding the silver into epoxy resin, with good thermal and adhesives properties.
As a result of good thermal-conductivity, mechanical properties and electrical conductivity, added with the simple structure, nano-silver solder has become the developmental orientation of high-power LED 's bonding and package technology.
However, due to the high thermal conductivity, high insulation properties, strong mechanical properties, non-toxic, and having similar hardness as Al, AlN substrate has a broad prospect on the application as a high efficiency LED's packaging material.

The fatigue test result indicated that the fatigue strength by the optimized technic was improved by 25%, compared to the anterior technic without optimization. 1 Introduction High Cycle Fatigue (HCF) is currently the primary cause of component failures in turbine aircraft engines, which serious affects the engines performance and flight safety [1].
Titanium alloys have been widely used in many applications including aerospace and aircraft industry because of their high specific strength, good ductility, and excellent fatigue properties.
According to the results of theoretical analysis, the LSP technic on the titanium simulated blades was optimized, and the fatigue property was improved. 2 Stress-strain distribution after LSP LSP technique shows different mechanical behaviors from static plastic deformation because the ultra-high strain rates (>106).
Consider the hardening rate is constant in the J-C model, Khan-Huang-Liang et al thought hardening rate decreased at ultra-high strain rates, and modified the J-C model, the specific form as follows [10]: （1） The equation indicates that the flow stress increase infinity with the increasing of strain rate, which is against with the regular of mechanical properties.
The fatigue strength of simulated blade was 410MPa after optimization, compared with the first process, increased by 25%. 5 Conclusion In this paper, the influence factors of residual stress fields were discussed based on the analysis of the shock wave propagation characteristic on the TC17 titanium alloy, the technic on the titanium simulated blades was optimized, and the fatigue strength was assessed by the high cycle vibration fatigue test.

Factors controlling this behaviour are reviewed.
The mechanical properties of scales and their adhesion are reviewed.
Properties of steam grown scales This section will review properties of the steam-grown scales and will include transport properties, mechanical properties as well as relevant physical properties.
Mechanical properties.
Thermal properties.

But in the design of interface, the assumption is made that the shear is uniformly undertaken by shear stubs, neglecting the chemical cementation force, mechanical joining-up stress and effect of contract friction.
This assumption is uninfluential to the whole performance of the bridge, but has a major impact on the arrangement of shear stubs which is affected by the friction on the interface and the shear distribution of shear stubs in their group.
To study how friction on the interface affects the property of the joining section, three models are made in this paper.
Fig.7 Shear of stubs in middle column Fig.8 Shear of stubs in edge column Fig.7 and Fig.8 show the shear distribution of the stubs is identical in three models to the steel-concrete interface, and the stress of model 2 and 3 is a little smaller than the model 1 in which contract is neglected Conclusions The chemical cementation force and mechanical joining-up stress were not taken into account in this paper, because of the capability of FE soft and complex affected factors which are hard to determine without sufficient experimental data.
The consideration of contract to steel-concrete interface is negligible to Mechanical Behavior of steel and concrete box girder in the bridge. 4.

This paper examines the mechanical properties of reinforced thermoplastic pipes (RTP) under the influence of external pressure.
However, prevalent work on the mechanical properties of RTP has mostly used laminated plate theory combined with the finite element model and experimental approaches, and has ignored the nonlinearity and interlaminar stress of the material.
Because the functional units were used only for signal transmission and did not affect the overall mechanical properties of the RTP, they were not considered in the mechanical model.
When the winding angle was greater than ±50°, the compression properties of fiber could more fully manifest, the fiber compression fracture occurred.
Effect of temperature on tensile properties of reinforced thermoplastic pipes.

However, in practical straight bevel gears drives, gear damage including wear, surface fatigue, plastic deformation and breakage may occur because of long working time, deterioration of the environment and other factors [6,7].
In fact, contact pressure is the key factor affecting wear [16-18] and investigating the contact pressure in straight bevel gear meshing is very significant to understand the gear wear mechanisms.
The material is 40Cr steel with the properties of Young’s modulus E =206GPa and Poisson’s ratio =0.3.
Liu: Mechanical Science and Technology.
Han: China Mechanical Engineering.

However, when it is exposed with fire at high temperatures, the mechanical and physical properties of concrete have changes certainly.
It depends on a number of factors such as the position of the structure and the internal force level of the structure, concrete type, aggregate type, etc., concrete spalling certainly occur.
Therefore, this is considered as one of the basic factors to be recognized to consider and evaluate the levels of damage to the structure after a fire.
Results and Discussions Engineering properties of the ternary-blended geopolymer are shown in Table 1.
Pham, Engineering properties of lightweight geopolymer synthesized from coal bottom ash and rice husk ash, AIP Conf.

The pore structure of a material radically infuences its properties, such as strength, freeze-thaw resistance, capillarity or resistance to elevated temperatures.
The amount, size and connectivity of the air voids and pores all have a strong impact on the physical and mechanical properties as well as durability of the hardened composites [1].
The total volume of pores depends on many factors related to the technology of cement composites.
Picture of a specimen with an addition of CA – 26 days after the application of CA [10] Materials and Properties The experiment described herein used a secondary crystallization additive designed for cement based mortars.
They had no influence on the average pore diameter (Tab. 2, 3), however, they did affect their distribution (Fig. 2).

Numerous research studies have been performed on mechanical properties of fiber concrete and concrete structural members reinforced with fibers under various loading conditions.
Because of the damping ratio of reinforced concrete structures change range is small, and there are lots of factors affect the structural damping ratios[[] WANG Suguo, The Effect of Slabs on the Failure Mode of Reinforced Concrete Frame Structures Journal of CiviI，Architectural&Environmental Engineering. 2009(2);V01.31 No.1:66-70. ], such as material damping, the surrounding medium, support style etc.
The vibration properties of the cantilever slab can be changed with slab quality, stiffness, overhang length, and damping etc.
By computing and comparing displacement and vibration frequencies it was found that overhang length and reinforcement diameters had much greater influence on structural properties.
Of course, there are complex factors influencing the displacement and vibration frequencies of the cantilever slabs, for examples, overhang length, reinforcing, elastic modulus, damping and mass, etc. 4.

Introduction Demands on Polyetheretherketones (PEEK) polymer start to increase especially on medical application because of its favourable high specific strength and biocompatible properties.
S. et al., 2001] Nowadays, medical device manufacturers are leveraging implantable polymers that have high performance and customized properties because those polymers capable to give high design flexibility which ultimately improve the applications [8].
The complex interaction between the matrix and reinforcement structure yield the gaps different between thermal and mechanical phase of PEEK.
Although the reinforce elements can improve the strength and stiffness properties, however the machining cost is high as reinforced PEEK is extremely abrasive.
The steepest curvature indicates the factor that most significantly affects the response, whereas the relatively flat line suggests insensitivity to change.