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As the remarkable feature of the Laser heat treatment process technology and the increasing of productions of the domestic laser devices, the laser heat treatment process technology was applied to the surface of the oil threaded to improve the integrated mechanical properties of oil pipe products and to extend its work life.
These technologies are very important to change the materials’ mechanical properties, heat resistance and corrosion resistance.
It has energy concentrated, rapid processing speed, small heat affected zone, little deformation, small follow-up process; 3.
It also go downs into underground deeply and is required higher strength and sealing, so the high precision and strength of connect thread are definitely requested , in addition , the shackle times is a important measurement factors of working life of pipeline production because of frequent well repaired .
Due to the outstanding feature of laser heat treatment technology and laser equipment production is more and more ripe in our country, laser heat treatment technology was used to deal with the surface of pipeline thread in order to increase integration mechanical properties and extend the working life .

Using the material density, the adhesive selection and the foam agent modification as main factors, and the cushioning properties as index, the molding process was optimized.
Meanwhile the mechanical properties were also investigated.
Sunflower stalk pith cushioning materials of biomass materials have been pre-treated for more than 24 hours and then for buffering properties and bending strength test.The above process can be illustrated as Figure 1 as follow.
In ensuring the cushioning properties of materials under the premise of the specimen density is 0.10g/cm3, MOR is 12.56Mpa.
The biomass obtained cushioning packaging material with good cushioning properties.

The fire behavior of the planar pre-stressed tubular steel trusses in which two cables are set is analyzed with the model presented here and the effect law of different factors on the bearing capacity of the structures in fire are discussed.
Introduction Pre-stressed steel structures with better mechanical behavior is a kind of special structures which has been widely used in practical engineering [1], but its overall performance will change greatly when fire happens because of its speciality.
The fire response and thermal expansion effect of the structure resulting from the change of material properties are considered in the model.
The effect law of different factors on behavior of the whole structures are discussed by analysis of bearing capacity of the pre-stressed steel trusses with two plans of cable-setting in fire.
(5) wherestands for the reduction factor, is elastic modulus of steel cable at room temperature.

The result shows that the mechanical properties of rocks near the bottom are subject to terrestrial stress, pore pressure and fluid column pressure.
According to the characteristics of mechanical properties of rocks in well, through the theoretical model and the finite element numerical simulation, analyze two-dimensional and three- dimensional force and find the reason for improving penetration rate, wall instability and deviation deeply. 2 The analysis of stress state and strength in surrounding rock near the bit The stress state in surrounding rock is the important factor of wellbore stability.
Rock crushing resistence ability can be affected by the changes of pore pressure.
So the bit crushing efficiency and penetration rate can also be affected.
The mechanical properties of the rock near the bottom in deep stratum underbalanced well are affected by the terrestrial stress, pore pressure, hole size and fluid column pressure and other factors. 2.

In this study, to clarify the material factors affecting the fatigue strength degradation by irreversible hydrogen, we conducted the fatigue tests for cold-drawn eutectoid steels having different activation energies or microstructures.
Table 2 Mechanical properties.
Table 2 summarizes the mechanical properties.
This implies that the irreversible hydrogen content itself was not a determining factor affecting the fatigue strength degradation.
Conclusion We investigated the factors affecting the fatigue strength degradation by irreversible hydrogen in cold-drawn eutectoid steels.

Meanwhile, an acoustic model was theoretically built on the transfer matrix method to calculate and analyze the influences of the coating loss factor, density, Young's modulus and the frequency on underwater acoustic absorption properties.
Polyurethane elastomer have good mechanical properties, damping properties, adhesion properties and wear resistance, and its performance can be adjusted by means of molecular design [6].
High adhesive strength castable polyurethane elastomer can overcome deficiencies of ordinary rubber poor adhesive properties with iron.
The impact of the adding of P(VAc-co-TAIC) macroporous resin beads and iron powders, and P (VAc-co-TAIC) macroporous resin beads hierarchical gradient structure and other factors to underwater high frequency(100 kHz ~ 300 kHz) acoustic absorption performance of coatings could be studied.
Conclusion In summary, this article showed that considerable means for improving the underwater high frequency acoustic absorption properties of underwater acoustic materials.

Initial imperfections on beam string structure (BSS) include geometric imperfections and residual stresses, which negatively influence the mechanical properties of BSS.
This paper analyzed the mechanical influences of initial imperfections on BSS by FEA, pointed out that initial imperfections do not remarkably influence the properties of BSS in stage of prestressing, but geometric imperfections obviously influence the displacement out of plane in stage of use, which should be controlled to improve the safety of BSS by installing enough lateral supports at the upper chords of BSS in construction.
Introduction The imperfections in beam string structure mainly include geometric imperfections and residual stresses, which negatively influence the mechanical properties of BSS according to general principles of steel structures [1], but researches about the problem are very scarce because of complexity of initial imperfections and high cost of analysis.
On this condition, designers generally neglect the negative influences of initial imperfections and simply leave some margin for their design to treat with the problem, which probably hides some dangerous factors in structure.
The fact of limited plastic development determines that the decrease of stiffness of BSS coming from plastic factor is not apparent so that the whole mechanic properties of BSS are not affected obviously.

A laminated plate with excellent mechanical properties is commonly used for a bulkhead part in which the interface structure of diffusion bonded is detrimental to the bending quality.
Laser cladding of metals is known to be capable of producing large area bonding between metal plates, including couples of those with grossly different mechanical properties.
The main parameters affecting the height of transition zone are the process speed and laser power.
Table 4 listed the mechanical properties of SCLP.
Guo, et al, Interfaces of titanium-aluminum clad sheet and affecting to processing performance, Xiyou Jinshu. 35 (2011) 342-348

The processing method for the polymer composite influences the properties of the composite including electrical and mechanical properties through the dispersion and orientation of particle during the production process.
Molding parameter such as molding time, molding pressure and molding temperature have proven will affect themechanical properties of the produced composite [14].
The Right molding parameter is essential to obtain acomposite with good mechanical properties.
Therefore, optimization process is critical to obtain nanocomposites with maximum mechanical properties especially for flexural strength.
Ferret, Effects of cure cycle pressure and voids on some mechanical properties of carbon/epoxy laminates, Compos 26 (1995) 509-515

The integrity and density of the barrier layer and the across-running cracks of the silicon carbide transition layer are the main factors influencing the oxidation resistance of the sample.
The strength retention ratio of different coating samples after oxidation under different temperature were calculated, and the effect of oxidation on mechanical properties of the coating samples was analyzed.
Results and Discussion Antioxidant properties.
Mechanical properties.
The integrity and density of the barrier layer and the perforative crack of the silicon carbide transition layer are the main factors influencing the oxidation resistance of the sample.