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Effect of reinforcements on the ultraprecision performance of SIC reinforced aluminium matrix composites Dazhen Wang1, a, Peifeng Feng2,b and Ling You3,c 1,2,3College of Mechanical Engineering, Jimei University, Xiamen 361021, China adazhenwang@163.com, bpffeng@163.com, cyouling85yoyo@163.com Keywords: aluminium matrix composite, ultraprecision machining, SiC reinforcements, deformation mechanism, surface roughness.
However, despite all these attractive properties, the commercial and industrial application of SiC reinforced aluminium composites is limited[6,7].
Table 1 Physical and mechanical properties of the specimens Experimental Materials Volume fraction of Reinforcements j [%] Density r [g.cm-3] Tensile Strength sb [MPa] Young’s Modulus E [GPa] Elongation percentage [%] SiCw/LD2 15 2.85 650 160.0 2.0 SiCw/LD2 25 2.88 660 165.0 1.7 SiCp/LD2 15 2.71 400 99.0 1.8 LD2 - 2.70 330 70 16.0 The Atom Force Microscope (AFM) is from American Digital Instruments Company, and the tapping mode and Si3N4 probe with a cone angle of 35° are used for examination.
The surface quality in the ultraprecision turning of aluminium composites with polycrystalloid diamond PCD tool is affected by a number of factors[17,18], which include tool types and their geometrical angles, cutting parameters, the mechanical properties of specimens and vibration of the lathe, etc.
Chan, C.F.Cheung: International Journal of Mechanical Sciences, 2001, Vol.43, pp 2047-2068.

These phase transformations have a detrimental effect on the fatigue properties of the welded structure, which is made worse by the presence of notch stress concentration and residual tensile stresses [3].
In order to improve fatigue properties of steel welded components, hammer peening may be performed [2].
In this work, those three factors have been studied in order to assess their respective influence. 2.
The analyses were performed in the longitudinal and transverse directions, in the weld toe (heat affected zone) or in the hammered zone of the plates.
Since in most cases the crack, which leads to mechanical failure initiates from the surface of the work piece, components with nano or ultra-fine grain superficial layers are expected to have improved fatigue properties because both fatigue crack initiation and propagation are inhibited by the presence of fine grains near the surface and coarse grains in the interior, respectively.

The auto claw-pole is made by low carbon steel, which has complex geometry and high requirement of mechanical properties (Fig. 1).
The modification induces a linear decrease of the consistency by multiplying it by a factor going from one zero between the solidus transition between semi-solid and solid behavior during cooling [8-10].
It can be seen that: DHTD is slightly affected by the initial billet temperature.
DHTD is quite measurable affected by die temperature, especially at low punch speed where the impact is quite clear.
Acknowledgements The authors are grateful to School of mechanical engineering of Xi'an Jiaotong University.

Flow Analysis on Hydrostatic Guideway of Precision CNC Lathe Based on FLUENT Li Song1, a, Song Jinchun2, b, Han Mingli3, c and Ren Yujie4, d 1, 2, 3, 4 School of Mechanical Engineering & Automation, Northeastern University, China alisongsnow@163.com, bjchsong@mail.neu.edu.cn, cminglihan1986@126.com, dyltryj@163.com Keywords: precision CNC lathe; hydrostatic guideway; FLUENT; flow field Abstract: In order to improve the machining accuracy of precision CNC lathe, and explore the fluid motion law in the closed hydrostatic guideway, three-dimensional model of hydrostatic oil chamber was established using preprocessor GAMBIT of FLUENT.
Introduction In the past decades, with precision machining technology widely applied in aviation, aerospace, mould making, etc., the machining efficiency and machining accuracy requirements of precision machine are highly increasing.[1] The guideway accuracy is one of the most important factors which affect the machining accuracy.
And pressure under-relaxation factor was set 0.3.
The three-dimensional image shows the pressure distribution is not homogeneous, which makes the real properties of hydrostatic guideway can be deeply recognized.

Studies revealed that human CHD-related mutations affect multiple factors that control cardiac development and such mutations often alter expression of multiple genes or gene products [4,9-11].
However, several Cx hemichannels remain close under normal physiological conditions and open in response to stress factors, such as sudden mechanical shock and specific physiological signals [32, 33].
In fact, hemichannel properties are being studied in laboratory setting by exploiting the fact that sudden mechanical shock, like dropping of liquid from certain height, can open Cx hemichannels located on the cell surface.
Bukauskas, Functional properties of mouse connexin30.2 expressed in the conduction system of the heart, Circ Res 96 (2005) 1169-1177
Spray, Properties of gap junction channels formed by Cx46 alone and in combination with Cx50, Biophys J 79 (2000) 1954-1966

Most of the research undergone up to now investigates such properties in bulk materials.
Some other basic properties, apart from the transformation temperature, of the stoichiometric NiTi alloys can be also found elsewhere [5, 6, 7].
As chemical composition is then critical for the shape memory properties, all melting processes must be done in a vacuum or an inert atmosphere in order to avoid the reactivity of the titanium in these alloys.
Factors that may influence the transformation temperature are: (i) Ti-rich and Ni-rich compositions (these show respectively NiTi2 and Ti3Ni4 precipitates) where excess nickel strongly depresses the transformation temperature and increases the yield strength of the austenite; (ii) common contaminants such as oxygen and carbon (Ti4Ni2OX and TiCXNi1-X) can also shift the transformation temperature and degrade the mechanical properties and, (iii) the elimination of local stresses after a heat treatment produces an increase of the transformation temperature.
Hodgson, Shape Memory Alloys, Properties and selection: nonferrous alloys and special purpose materials.

Whether the performance of corona discharge is good is a key factor for dust removal.
The experiment content is as follows: (1) to measure different characteristics of spray of different atomizing nozzles by taking water as the working medium; (2) to study on the discharge current affected by water mist; (3) to choose an optimal nozzle which has a good combination property.
Droplet diameter affected by water pressure (a) Solid nozzle (b) Hollow nozzle Fig.4.
Fig.6 Collection efficiency affected by solid nozzle Fig.7.
Collection efficiency affected by hollow nozzle Fig.8 shows dust removal efficiency affected by the dust particle size.

The normal stress between wires is one of the main factors of the slipping and stress concentration in the stay-cables.
Otherwise, the effect of frictional stress between steel wires must be taken into consideration during the analysis of stay-cable's bending property.
In this problem, the friction factor can be confirmed by test, so the key procedure is accurately calculating the normal stress between the steel wires when they are subjected to the longitudinal force.
(i) Normal stress caused by the lay angle ((KN/m) Normal stress caused by the PE protection (KN/m) Frictional factor* Maximum static friction (KN/m) 1 378.88 35.578 0.211 87.42 2 802.34 35.578 0.211 176.74 3 1282.26 35.578 0.211 277.97 4 1836.01 35.578 0.211 394.77 5 2490.44 35.578 0.211 532.81 6 3290.31 35.578 0.211 701.52 7 4318.70 35.578 0.211 918.44 8 5758.45 35.578 0.211 1222.12 9 8158.04 35.578 0.211 1728.26 10 15356.81 35.578 0.211 3246.68 * Measured by the friction test Fig.5 The tendency chart of the static friction force between layers 5.
Conclusion Normal stress will be generated due to the spiral angle of wires and pinch-effect of hot-extruding PE wrapping when the stay-cable is under longitudinal force, it will ultimately affect the local cable bending stresses.

In order to improve the performance of Love wave sensor, the theoretical relationship of TCF on substrates and guiding layers temperature properties is researched.
Effective sensitivity of Love wave sensor is affected by temperature.
Practically such a reference setup can reduce the TCF by a factor ten or higher.
Firstly, we probed into the relationship between TCF and temperature properties of substrate and guiding layer, and the pattern of temperature compensation.
So in this presentation we studied the pattern in which the substrate and guiding layer affect TCF of device.

Sun 1 1 College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, China a Luwz991@sina.com.cn Keywords: Diamond Film; Stress; Large Area; Freestanding Abstract.The present paper describes research on stress in freestanding diamond thick film, diameter of 60mm, prepared on Mo substrate by DC arc plasma jet chemical vapor deposition (DCPCVD) method.
Introduction Chemical vapour deposition (CVD) diamond is finding increased application where the exceptional properties attained by diamond are required.
The effect of stress in freestanding diamond film mainly presents as: (1) Internal stress can easily cause film cracking or fracturing during deposition process; (2) Internal stress induces machining crack during machining process; (3) Internal stress causes mechanical or optical connection failure on cutting tool or optical windows.
Fig.3 Stress in CVD diamond film measured by XRD Fig.5 Stress calculated by Raman peak shift The main factors which affect the residual stress in CVD diamond film include the content of sp2 carbon, grain boundary compositions and material defects.
Lu, D.Zuo, M.Wang: J. of China Mechanical Engineering Vol.15 (2004) No.18, p1676 [2] W.Z.