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And as a kind of important micro mechanical transmission components, micro-gear has important application value.
Micro-gear is an important micro-part and has great potential application in mechanical transmission.
The microscopic effect can be shown in two aspects: the size effects of physics laws and materials properties[1].
DAI et al.[5] compared the forming processes of different injection materials such as ABS, PP and PC, including the main process parameters affecting the micro-parts quality such as injection pressure, mold temperature, injection temperature and filling time.
Table 3 Processing parameters of the material Manufacturer Ejection temperature [℃] MFI (230℃, 2.16kg) [g/10min] Glass temperature[℃] Melt temperature[℃] (recommended) Mold temperature[℃] (recommended) Omsn 145 53 100.69 190-270 20-50 Results and discussions The dominated injection factors are examined and adopted among these parameters, such as melt temperature, mold temperature, injection time and packing time.

Generally it is necessary for micromachined accelerometer system to compensate for the phase lag caused by poles of mechanical element and interface itself[1].
Fig. 1 Sensor element equivalent math model It is obvious that sensor element is characterized as 2nd transfer property.
Root locus of 2nd-order ΣΔ micromachined accelerometer shows that eigenvalue of 2nd-order system always exist at left half-plane with different quality factors.
Thus, the system is not sensitive to variation of quality factors.
Figure 3 shows the relationship between SNDR and compensation coefficient in 2nd-order ΣΔ system (quality factor is 0.86).

Statistical parameter for different loads of load combination Types of load Permanent load Office live load Live load of residence Wind load Mean value 1.060 0.700 0.859 0.999 Coefficient of variation 0.070 0.290 0.233 0.193 To obtain the uncertain factors about calculation model, the ratio of measured value over calculated value for the bearing capacity of members is needed, and then the mean value and variation coefficient can be calculated and mean value of uncertain factors about calculation model (µKP) and variation coefficient (δKP) can be finally obtained.
Table 3 list the uncertain factors about calculation model of cold-formed thin-wall steel structure under axial compression, flexure, eccentric compression condition.
Since the members studied in this paper have superior mechanical property, the failure is defined as ductile failure and the value of [β] is 3.2.
Journal of Chongqing architectural engineering institute . 1985(1): 36～41 [3] Guoxin Dai, Longchun Li, Zhenzhong Xia etc. building structural steels new material properties statistics and analysis of .
The Calculation of The Residual Stresses Affecting The Whole Stability of The axil Center Pressure Bar of Thin-Wall Shaped Steel .

Table 1 The mechanical property of tube blanks.
The mechanical property of tube blanks is listed in Table 1.
There are a large number of factors that affect the quality of the products in the hydropiercing process including technical, material and geometrical parameters.
According to Eq. 7 corresponding to the roll-over depth, only the first coefficient (internal pressure) affects apparently and the effects of the other three factors are very small.
Then the interaction of these two factors should be researched.

SiCp aluminium-based composites possess a combination of novel properties including good wear resistance, high thermal conductivity, low expansion coefficient, low density as well as high mechanical strength[1-4].Besides, the preparation of SiCp aluminium-based composites is simple, cheap, development rapid and wide application make it become the focus of research in the contemporary emerging material field [5,6].Because aluminum and SiC particles have huge difference at the aspect of physical and chemical properties, poor weldability become the main factors which prevent its application [2].Research shows that nickel plating on the surface of SiCp aluminium-based composites can increase its weldability [6,7].
Due to difference at the aspect of physical and chemical properties between SiC particulate and aluminum alloy matrix, the characteristic of joining the composites is distinct from aluminum alloy matrix.
Temperature and holding time are key factors in vacuum brazing.
While the solder can melt completely if the holding time increases and the interaction between solder and composites will intensify and the SiC particulate of solid-state gathered further in the interface of joint, which will have negative influence on the properties of the joint.
Holding time affect the hardness of weld joint.

Improved insulation properties may be achieved by incorporation of thermal insulation materials, whereby increasing the loading would improve the overall insulating properties.
In general, the mechanical properties of concrete are enhanced by a reduction in water/cement ratio (w/c) or improvement in packing densities.
Mechanical strength properties of cured AIC samples were measured according to DIN EN 196-1 standard [6].
Results and discussion Physical properties of AIM samples.
The physical properties of the cured AIM samples after 28 days were analysed first.

Moreover, the fatigue factors are discussed so that researcher can get little idea about failure point of the nickel-titanium rotary files.
The nickel-titanium alloys are used as bio-compatible material in Endodontics over the stainless steel because of its mechanical properties and geometry viz. shape memory property, higher super elasticity, flexibility, lower elasticity modulus than steel, taper and narrowness in curved canal proved to be efficient for canal preparation [5].
There are three important factor related to fatigue life viz. fatigue damage, fatigue safety factor, fatigue sensitivity factor etc.
Fatigue safety factor represents factor of safety value related to design life.
Yared G, In vitro study of the torsional properties of new and used Pro File nickel titanium rotary files, J Endod. 30 (2004 ) 410–12

It is found that the full state function can more comprehensively reflect the properties of the structural material.
The elastic properties of the materials mainly refer to the properties and characteristics of the materials when the morphology of the material remains unchanged.
However, the plastic properties of material in the macroscopic sense are the manifestation of the properties of material in the process from one structural state to another.
In the classical elastic-plastic theory, the methods describing the plastic properties are mainly divided into strength theory and constitutive relation.
The structure of the material will change when influenced by environmental factors, that is, it will shift from one structural state into another.

Within manufacturing processes, the surface condition is characterized by geometrical aspects and by properties of superficial layers.
The properties of superficial layer analyzed in order to define the surface condition are the microstructure, the microhardness and the superficial residual stresses.
All these characteristics of surface layer could be affected by machining processes applied in order to obtain a certain mechanical part and, one the other hand, they strongly affect the service life of mechanical part.
In fact, the characteristics of the surface layer are properties taken into consideration when the quality of a certain product is evaluated.
In the future, there is the intention to obtain an improved classification of the machining processes on considering their common and distinct properties.

Properties of High Pressure Water Hydraulic Components with Modern Coatings Janusz Pobędzaa, Andrzej Sobczykb Institute of Machine Design, Cracow University of Technology, al.
Cylinder friction force is varied and depends on few factors like: cylinder velocity, pressure and temperature.
The first stage of research was dedicated to determine properties of singular cartridge valve 2-URES-6 installed in two way body.
The use of water reduces pressure losses by half, positively affecting energy efficiency of the high pressure water hydraulic system.
Covering the inside surface of the cylinder and the piston and piston rod surface confirms the protective properties of novel coatings against corrosion of steel parts, together with acceptable values of hydro-mechanical efficiency, not different from characteristics of oil actuators.