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For pipe thread sealing research, points dynamic and static two direction, static mainly from internal and external thread fit method, material hardness, geometry size, pipe thread bottom and top of tooth shape, packing, etc factors to hands and dynamic stress concentration is the main research, stress relaxation and high temperature oxidation on the pipe thread seal influence [1].
Due to the load properties (including load type, size, distribution, direction, etc.) kaleidoscope, relative displacement also is not only the tangential, radial, rolling and twist simple way, and may be two or more basic model compound complex movement.
Thread structure in mechanical vibration, etc.
Conclusions According to the analysis of the above situation, it is known that in consideration of the environmental gas composition, high temperature, humidity and corrosion medium, affect pipe thread micro damage and micro fatigue strength and life of the main control parameters are: contact surface and the region near the stress field, namely the size and distribution of the stress situation; in the load cycle, the contact surface of the relative sliding on the size and distribution of the momentum; contact surface friction coefficient;material properties.
In view of the above factors, in order to improve pipe thread sealing performance, the actual should be paid attention to in the application from three ways: enhance the internal and external thread type and size of the processing requirements, make its as far as possible consistent, but there are certain limit, namely in the economic and the possible conditions guarantee in a certain tolerance range; inside and outside threaded and after, through some tightening torque make internal and external thread itself materials produce certain deformation to fill a part of the clearance; between the inner and outer thread has plasticity to join the packing.

Tooth surface appeared more obvious gray spots, in severe tooth surface material would emerge large spalling, cracks and even broken teeth [3].There was many factors which caused gear tooth wear but the most important wear mode of them was fatigue wear, adhesive wear and fretting wear[4].
The Calculation and Analysis of Involute Helical Gear Wear According to the theory of integrated wear[5],the fundamental principles of integrated wear calculation was that the allowed position change quantity of mating surface was determined by mechanical parts working performance ,that was integrated wear, which then derived the wear life of mechanical parts in consideration of gear indexing accuracy and smooth transmission.
Considering some factor impacted on gear wear, such as the tooth surface characteristics, lubrication conditions, working conditions, etc, the coefficient,,were introduced, then the normal line wear value of gear was: (13) Then, the total normal wear value of gear pair in the running period could be obtained
Therefore, as the wear life calculation or anti-wear design was carried out, some influencing factors should be taken into account, such as the gear material properties, surface characteristics, technological parameters, gear lubrication condition, operating status, which should also be collected from extensive test data and could be used to modify models more practical.
Mechanical Research & Application, 2009,(6):50-54.

The most widely used Ti-based superalloys is Ti-6Al-4V which belongs to the α-β group because of its high strength properties at elevated temperature up to about 300ºC [1, 2].
Although titanium alloys have been classified as difficult-to-machined-material, its properties such as low thermal conductivity and strong affinity to tool materials can cause rapid tool failure and short tool life.
Previous researches on machining titanium [3, 4] had showed that the surface integrity of the machined surface components can be affected and resulting in reduction of the service life.
Beside the point angle, other factors also influence the surface finish or smoothness of the drilled holes such as different lip height, style of the drill point, helix angle and size of the margin and rigidity of the drill.
Another factor that influences the degree of deformation is the point angle of tools.

However，the properties such as high accuracy，excellent reoeatability and so on are not included in the advantages.
The quality factor is an important parameter for dynamics of the cantilever.
Summary We have discussed the static and dynamic properties of the mcrocantilever and the ways to improve the sensitivity of mcrocantilever.
Mechanical behavior of ultrathin microcantilever[J].
Mechanical quantity sensitive device and its application [M].

Under the impact of environment, climate, conservation conditions and other factors, forms of bridge disease vary in different areas.
However, affected by load capacity, environment and material deterioration, as well as other factors in design and build, bridges are suffering from various kinds of diseases during their construction and use[1].
(2)Reasons for Bridge Diseases 1) Beam Bridge Reinforcing bars rustiness is an important factor that causes damage in reinforcing bars and concrete elements.
Considering environmental factors in Nantong, starting from disease analysis, this paper has studied the maintenance strategy according to the type, extent and causes of concrete bridges diseases.
When we repair a bridge, it’s necessary to consider not only the s mechanical characteristics and material properties, but also the construction convenient and the traffic. but also consider the economic constraints and many other conditions.

., mechanical overload), or an abnormality of the underlying subchondral bone [5, 6] are the main detailed factors to produce articular cartilage lesions.
Scaffolds can be used either alone or as delivery vehicles for cells, mitogens or growth factors
It contains key components such as type II collagen, proteoglycans, and additional cartilaginous growth factors.
Moreover, such materials should be able to support cell growth and proliferation, incorporate growth factor and present appropriate mechanical properties during all the tissue regeneration process.
Khademhosseini, The mechanical properties and cytotoxicity of cell-laden double-network hydrogels based on photocrosslinkable gelatin and gellan gum biomacromolecules, Biomaterials 33 (2012) 3143-3152

This paper presents the effect of Er on the microstructure, mechanical properties and thermal stability of aluminum alloys.
Up to 90% grains has high Schmid factors (>0.40).
Grains with high Schmid factors and low Schmid factors are randomly distributed in the alloy, increasing large deflections of crack propagation path.
The effect of erbium on the microstructure and mechanical properties of Al-Mg-Mn-Zr alloy.
Effects of rare earth element Er on structure and properties of Al-4Cu alloy.

Thermo physical properties of Copper/Diamond composites fabricated by Spark Plasma Sintering A.R.
Effects of different sintering temperatures on density of composites. 1.1 Thermo physical properties measurements and analyses Sintering temperature highly influences the T.C of the composite (Fig.5 a), however the basic factor, which affects T.C is copper /diamond interface.
These properties are highly influenced by the SPS temperature.
Thermal properties of diamond copper composite material.
Densification and mechanical properties of TiC by SPS-effects of holding time, sintering temperature and pressure condition.

The water uptake capability and the weight loss were measured up to 14 days and their mechanical properties were assessed with compression tests.
The mechanical properties were assessed using compression tests in dry state (Instron 4505).
This can be explained by two possible factors; (i) the formation of a siloxane network which prevented the material to degrade faster and (ii) due to different surface area of the porous structures.
These results may be explained by the change on the size and CS CST1 CST2 CST3 CST4 0 10 20 30 40 50 Weight loss (%) (B) CS CST1 CST2 CST3 CST4 0 200 400 600 800 1000 1200 1400 1600 Water uptake (%) (A) orientation of the pores (see Fig. 1) which affected the final mechanical properties of the porous materials.
Fig. 4: Mechanical properties of chitosan-soy protein (CS) and chitosan-soy protein/TEOS (CST) hybrids obtained by compressive tests: modulus (A) and percentage of maximum strain (B).

Although complicated control of parallel mechanism is avoided and development costs can be reduced with this mode, intended functions of CMM can not be fully realized. 3) As 1st slider and 3rd slider can not be complete stretched with 1000mm precision guide, the space of z<280mm can not be reached by probe, the actual measuring space is less than the scale of theoretical and unable to fulfill the expect technical indicators. 4) During measuring process there is interference in cardanic joints, and existd a larger clearance, measuring accuracy is difficult to get assurance. 5) It is irrational in material selection of key components of prototype and weak in the mechanical properties of overall, especially the mechanical deformation of beam and precision guide directly affect the measuring accuracy of CMM.
Schematic diagram of parallel mechanism CMM In order to enlarge the measuring space of CMM, improve the measuring accuracy and mechanical properties of CMM and flexibility of moving platform, structure of new prototype with active motion were optimization designed according to the structure parameters of previous one.
The beam is the key mechanical component of CMM and equipped with precision guide and grating, its deformation directly affects the measuring accuracy of the instrument.
The bar module is consisted of 2 cardanic joints and a carbon fiber connecting bar; cardanic joint is made from alloy steel and the material properties of connecting bar is as follows: modules is 3×105MPa, Poisson ratio is 0.25 and density is 1800kg/m3.
The key structure parameters of CMM and poses of cardanic joints were optimization designed; the measuring space of new prototype is 1050mm´535mm´426mm and enlarge 92% measuring space in x axis, 134% in y axis and 113% in z axis compared with the previous one. 2) The deformation of the key components are analysed by FEM, and the basic mechanical properties evaluation of the prototype is completed: the maximum deformation of beam δ1max is 61.86μm, and 0.778μm of the maximum δ2i.