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In the current paper, the microstructural inhomogeneity and the deterioration of mechanical properties in a thin-walled telecom component made by SSM-HPDC in a low Si-content aluminium alloy were investigated.
Two typical shear bands; (a), (b) eutectic rich band and (c) porosity band Mechanical Properties.
In this study, to investigate the effect of inhomogeneity on the mechanical properties and fracture behaviour in the cast compounds, three samples were taken from location 1, 3 and 5 of each component (Fig. 1).
Increase in the yield stress value in the sample from location 5 with the finer microstructure due to higher liquid segregation (Fig. 2(b) and 2(d)), highlights the effect of microstructure morphology on the final mechanical properties.
Mechanical properties in the semi-solid state and hot tearing of aluminium alloys.

Helium-Injection Cooling of Hot Silica Glass Fiber in Optical Fiber Manufacturing System Dongjoo Kim1, Il-Seok Oh1, Ho Sang Kwak2, and Kyoungjin Kim2,a 1Department of Mechanical Engineering, Kumoh National Institute of Technology 2Department of Mechanical System Engineering, Kumoh National Institute of Technology Gumi, Gyeongbuk 730-701, Republic of Korea akimkj@kumoh.ac.kr Keywords: Optical Fiber Manufacturing, Glass Fiber Cooling, Helium Injection, CFD Analysis.
The results found that the amount of air entrainment at the unit inlet is the significant factor that decides the cooling effectiveness by significantly lowering the helium purity in cooling gas.
Also, inadequate fiber cooling could adversely affects the optical quality and fiber strength of manufactured optical fibers [2].
Since the air entrainment into the cooling unit through the inlet is inevitable and it could be significant depending on fiber drawing speed, cooling gas is considered to be the ideal gas mixture of helium and air and its properties are evaluated by simple ideal gas mixing law.
Therefore, helium purity depending on the air entrainment and helium injection is the deciding factor in cooling effectiveness of glass fiber cooling unit.

(6) where ωm is the mechanical angular speed, Nph is the number of turns per phase, Kwn is the winding factor, Bpk is the amplitude of airgap flux density, D is the airgap diameter, L is the motor axial stack length, and Ipk is the peak phase current.
Motor with 18-slot/16-pole configuration is selected due to highest winding factor and to reduce the effect of cogging torque.
It shortens the magnetic flux pathway and allows the maximum magnetic properties of stator core during the motor operation without permanently magnetized it.
This is calculated based on the 0.9 T amplitude of airgap magnetic flux, 100 mm motor axial length, 106 mm airgap diameter, 120 number of turns per phase, 0.960 winding factor, 750 rpm motor angular speed, and 10 A peak phase current.
The motor performance is affected by adjusting stator tooth width nearly to the saturation level of the stator core hysterisis level.

Dynamical system modeling Through variable screening, the parameters that mainly affect vehicle following behavior are speed difference, vehicle distance and speed of the preceding car [6].
Road condition is good, adhesion is large enough, and the nonlinear factor of tire slippage is ignored. 3.
From the process of modeling above, established vehicle longitudinal dynamic system model can meet the requirements of simplicity, and can be realized with common vehicle technical data and a common software platform, and it also reflects the longitudinal dynamics properties of the actual vehicle system.
Because driving behavior is easy to be affected by human factors and traffic environment, the collaborative study of human - vehicle - road closed loop system has been one of the key research direction of ITS.
[3] Guanguli A, Rajamali R: Proceedings of the Institution of Mechanical Engineers.

Introdution Source cathode composition design in multi-element surface alloying by double glow plasma technique is the key factor to determine the composition of surface alloying.
The surface properties can be greatly improved by Cr, Mo.
Based on all of the factors above, source cathode only added the element Cr, Mo without V, Si.
According to Fick’s law, the solid alloying process is affected not only by temperature and time, but also by the solute concentration.
Because CrO3 has better thermal stable than MoO3.These characters affected Cr ion sputtering to some extent

- Level II (normal assessment): this is applied to those cases where the mechanical properties and the crack geometry in the component are known, but the Weibull parameter m is not available.
These properties are explained in terms of 1) the effect of YR on stress fields for the wide plate and toughness specimen and 2) a volumetric effect of m on the Weibull stress sW [3, 8].
It was assumed that the heat-affected zone (HAZ) has the same strength as the base metal (BM) or 10% higher strength.
On the other hand, the stress field in the HAZ for FL crack is affected by the strength mismatch: overmatch condition induces a constraint activating the HAZ stress field
The procedure to determine the correction factor r is given in Annex R in BS 7910.

The material structure cannot assist in the arrest of the large energetic cracks other than locally affecting the crack path.
We will consider the compression test as structural test since the outcome is very much dependent on boundary conditions, size, shape and other structural factors.
The flexural strength is also affected and decreases with increasing foam content.
Material properties must therefore be determined at a smaller scale than the above described cube compression test; nevertheless all the same constraints are met and one is never certain whether the adopted properties are true material properties.
-K. and Van Mier, J.G.M., Fracture of Foamed Cementitious Materials: A Combined Experimental and Numerical Study, in Proceedings IUTAM Symposium on 'Mechanical Properties of Cellular Materials', (Zhao, H. and Fleck, N.A., eds.), LMTCachan, Paris, France, September 17-21, (2007), Kluwer Academic Publishers, Dordrecht (in press)

In our work, this paper discusses atomization phenomenon and generalities based on the physical properties of liquid dielectrics.
Theoretical analysis Usually, jet length and atomizing angle are the main factors used to describe the effects of liquid atomization.
In the transient area, because the charged jet is disturbed by exterior factors, vibration periodically occurs on the jet, influenced by the liquid surface tension and the jet inertia.
Table 1 Contrasting properties of liquid dielectrics Liquid dielectric Surfacetension/ 10-3N•m -1 Viscosity/ MPa•S Conductivity/ S•m -1 Kerosene 10.42 72.93 1.27×10-12 Emulsifier 56.84 1.27×103 4.26×10-5 Alcohol 22.55 47.26 3.84×10-8 Design of the spraying nozzle.
Gao: China Mechanical Engineering, Vol. 13(2002), p. 552-554 (In Chinese)

As zinc (Zn) and calcium (Ca) are non-toxic and recognized as nutritionally essential elements in the human body, in this study Zn and Ca were selected as alloying elements to produce suitable bio-corrosion properties.
The effects of microstructure on the corrosion properties have been discussed previously, e.g., the influence of Mg17Al12 (β) in AZ91 [10,11].
The heat treatment affects greatly on the micro-galvanic corrosion between the anodic Mg matrix and cathodic second phases.
Chen, Microstructure, mechanical properties and bio-corrosion properties of Mg-Si(-Ca, Zn) alloy for biomedical application, Acta Biomaterialia 6 (2010) 1756-1762
Manuel, Investigation of the mechanical and degradation properties of Mg-Sr and Mg-Zn-Sr alloys for use as potential biodegradable implant materials, J.

From the author's systematical experiments [5,6,7,8], it is found that the theory having only viscosity function like a so-called over-stress constitutive model [2,3], can not explain a transient phenomena in flow stress which are observed at a sudden change in strain rate, and that the viscosity function derived from flow stress properties does not necessarily coincide with the viscosity function obtained from relaxation properties.
In this report, both cyclic loading dependence and temperature dependence of the two factors: viscosity and aging properties are investigated experimentally and systematically over a temperature range of -35͠ to 200͠.
Basic concept of the proposed two factors constitutive model Viscosity of materials has been generally connected with strain rate and work hardening.
Results and formulations of viscosity and aging properties Effect of strain rate on stress-strain curve around yielding.
On the basis of the two-factor constitutive concept, g curve should be replaced by f curve, because g level is affected by aging depending on strain rate.