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Study of the Wall Slip Effect on Viscous Fluid Micro-extrusion Process Congping Chena, Xiaoyun Wangb, Jieguang Huang College of Mechanical and Power Engineering, China Three Gorges University, Yichang, 443002, China aemail:mechencp@163.com, bemail:acuando@sohu.com Keywords: Wall Slip; CFD; Flow Rate; Fluid Expansibility Abstract.
In micro-scale flow condition, the flow rate and fluid extrusion expansibility are always affected by the wall slip between the fluid and tube wall.
The results showed that wall slip make the fluid resistance and expansibility decrease, and the fluid mass flow rate increase. 1 Introduction With the development of micro-electro-mechanical systems (MEMS), scale-effect on micro-tube fluid flow has been drawn wide attention [1], in which the fluid dynamics are significantly different from macro-flow[2].As the study shows, factors such as wall slip, surface tension, viscous dissipation that are always neglected in macro scale can impact micro-extrusion seriously.
Particularly, wall slip is one of the key factors which would decide the flow behaviors [3] like velocity, flow rate, expansibility etc.
References [1] Sun Daoheng, Gao Junchuan, Du Jiang, Jiang Yiwen, Tao Wei,Wang Lingyun, Advances in fluid dispensing technology for micro-electronics packaging, China Mechanical Engineering.22 (2011) 2513-2519

The use of HA coatings on titanium alloys leads to a structure that has good mechanical strength and good osteointegration properties at the surface and in the manufacturing of prosthetic devices.
The system HA/Ti is used to improve the surface properties of the device and to induce osteointegration process [8,9].
Another important factor to be considered is mechanical stresses.
Fig. 3d presents HA/Ti-6Al-4V cross-section which may give an overview of the possible impact of the morphology in the mechanical properties of the coatings and offer information directly related to their bond strength performance [43].
PS coating implant devices with HA the presented disadvantages some affecting the long-term stability and lifetime of implant.

Due to the irregularity of inner hole of flat receptacle, inconsistent resistance of shrinking fitting affects the inner hole within which nonuniform deformation occurs.
Considering the processing and assembling factors, we adopt the elliptical outer layer and circular inner layer as the new structure.
Due to the irregular shape of inner hole of flat receptacle, inconsistent resistance of shrinking fitting affects the inner hole within which nonuniform deformation occurs.
Inputs to the FEM simulation were thermal properties and flow stress for receptacle material and process information (pressure, ambient temperature and steady-state receptacle temperature).
The other method is not to directly provide the explicit definition of optimum parameters, while it uses the properties distribution of analyzing object as the optimizing object.

(B) Stability safety factor method: Stability factor is defined as the crane suffered various loads generated on the edge of the stability overturning torque and overturning moment ratio.
Stability safety factor as a crane anti-overturning capacity criterion cannot be less than the specified value.
Thus, the same crane stability factor may be different.
Design variables (1-8) are related with overall design of a truck crane, affecting the stability of crane.
Normal distribution has many good properties, has been widely used in mechanical reliability design and analysis.

Bisson et al. made apparent thermal conductivity measurements on monolithic silica aerogels and divided low-density xerogels, and establish a compromise with respect to the solid content of a xerogel in order to maintain a low thermal conductivity while ensuring sufficient mechanical properties.
In their study, laser remelting was combined to thermal spraying in order to modify the thermal barrier coating properties [4].
Low cost obstructive inorganic mineral insulation materials developed rapidly due to historical and socio-economic conditions and other factors.
The optical properties of the foils were compared with theory, and good agreement was achieved for pigment volume fractions up to 0.1.
Research Orientations Related to Thermal Insulation Materials The thermal insulation performance of materials is affected by many factors.

Though there are many kinds of mechanical components which are subjected to torsional load, few reports have been observed referring to the effect of plastic deformation on torsional fatigue properties [5,6].
Tables 1 and 2 list the chemical composition and the mechanical properties of the material, respectively.
Mechanical properties σB [Mpa] σY [Mpa] El. [%] 495 298 64.7 σB, Fatigue strength, σY, Yield strength, El., Elongation ratio � � Table 1.
The shape of the rigid element and the properties of the material were applied to the model according with the practice use.
This affects the compressive residual stress of axial and radial direction.

Among the possible disasters, fire is the greatest threat to people's lives and property owing to its random occurrence and low controllability.
In mechanical smoke extraction system, exhaust vents disposition and exhaust velocity will affect smoke spread [1~3].
Mechanical Ventilation System The subway station is a two-layer island type station.
The mechanical ventilation system will change into smoke exhausting system when fire happens.
Conclusions In the case studied, temperature and poisonous gas have little influence on safe evacuation of passengers, and visibility is the main factor.

At home Xu Tian, Yong Li and Jun Xiao trial-produced the X-cor sandwich and researched its molding process and basic mechanical properties[6, 7].
Jijun Hao, Zuoguang Zhang and Lei Zhang researched the effects of Z-pins inserting parameters on the compressive properties[13, 14].
Because the mechanical properties of resin regions are weak so the resin regions will fail firstly.
After the interface elements fail, the mechanical properties of sandwich decrease.
Fig.3 Propagation of the Z-pin tip failure elements (a) εz=0.0110 Fig.4 Propagation of the resin region failure elements (a) εz=0.0120 (b) εz=0.0111 (b) εz=0.0121 As the resin region elements fail the constraints of Z-pin tips weaken and the mechanical properties of X-cor sandwich are affected greatly.

Shape memory alloys (SMAs) are commonly used in micro-electro-mechanical systems (MEMS).
Having the unique shape memory, super-elastic affects and now damping capacity SMAs have become an important smart material for a broad range of engineering applications in last year’s.
Copper based SMAs are promising alloys, based on the obtaining price and good characteristic properties.
Jang, Effect of grain refinement on phase transformation behaviour and mechanical properties of Cu-based alloy, Trans.
Rusu, Influence of some extrinsic factors on the two way shape memory effect of electric actuators, J. of Optoelec. and Advanc.

The results show that the charging voltage affects on the AlN content and the morphology of samples, significantly.
The mechanical strength of AlN is pretty high at room temperature and decreases slowly with the rise of temperature.
In addition, AlN is an important III–V nitride-based semiconductor with several excellent properties such as wide bandgap (6.2eV), high thermal conductivity (318-319 W/mK)[1] at low temperature, high volume resistivity, low dielectric constant, excellent thermal expansion coefficient and excellent chemical stability[2,3].
The quality of AlN powder is one key factor to prepare high-quality AlN ceramic.
Haseeb, M.R Johan, One dimensional cuo nanocrystals synthesis by electrical explosion: a study on structural, optical and electronic properties, J.