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Machining Technology of Ultrasonic Assisted Grinding for a Silicon Carbide Wafer Carrier Chia-Jen Ting1, a, Chi-Feng Chen2, b, Ta-Hsin Chou1,c*, Tsung-Cho Wu1, and Tsung-Hsin Lin1 1 Mechanical and Systems Research Laboratories, Industrial Technology Research Institute, Taiwan 310(R.O.C.) 2 Department of Mechanical Engineering, National Central University, Jhongl, Taiwan 32001(R.O.C.)
Introduction Silicon carbide (SiC) with several advantageous properties such as a high oxidation resistance, good thermal shock resistance, low coefficient of thermal expansion, high thermal and electrical conductivity, high hardness, and excellent wear resistance, is one of the advanced engineered ceramic materials.
The transducer converts high-frequency electrical oscillations to mechanical vibrations.
For the different diamond particle size and binding mode, it will affect the processing efficiency of the grinding wheel.
Four key machining factors are chosen: spindle rotation rate, UTH type, feed speed, and ultrasonic output power.

There are a variety of agronomic grafting methods; cut-joint method and insert-mating method are the most suitable methods for mechanical operation.
In addition, the fast motion of mechanical operation is also good at reducing water loss from the graft wound [3].
The straighter the stem is the more good to the success rate. (4) From figure9 we can see, cotyledon angle also affect the graft result.
The experiment errors are caused by the following factors: (a) the number of rootstock and scion is limited; (b) artificial measurement error; (c) error caused by data process method.
References [1] Y.C.Chiu, M.Y.Chang, G.J.Wu, C.C.Chen, Development of an automatic outward-feature properties measurement system for grafted tamato seedlings, Applied Engineering in Agriculture. 24(1): 101-113 [2] J.M.

CaP surfaces were observed to present differing morphologies and roughness (Ra) values that depended on either mechanical preparation or the use of a sputter deposited underlying titanium metal layer.
These in vitro studies also showed cell response to be significantly affected by the presence of the titanium interlayer.
Employing RF magnetron sputtering to deposit coatings of sub-micron thickness implies that the underlying substrate topography is a critical factor in defining the nature of the deposited bioceramic layer.
Hence, key coating properties, and thereby the resultant biofunctionality, may be significantly influenced by both the choice of sputtering conditions and the nature of the underlying substrate surface.
Key properties, such as surface roughness and contact angle have been determined and correlated with the condition of the underlying native substrate.

Polyurethanes are also non-toxic and crosslinking offers resistance to biological fluids so that mechanical properties are maintained.
Major factors affecting the thermal stability of polymers are: (1) Linkage isomerism [21] (2) Ring substitutions [22] (3) Linking groups [23] (4) Heterocyclic moieties [24] Metal-containing Polyurethanes Polyurethanes constitute one of the most complete and versatile polymeric materials exhibiting excellent mechanical and physical properties in spite of a major drawback in their poor heat resistance and acceptable mechanical properties (strength, moduli etc.) vanish at about 80-90 °C, while thermal degradation occurs above 250 °C [25].
Some of these compounds have mechanical properties similar to commercial liquid crystalline polymers.
Kevlar is mainly used for applications, where high mechanical performance and light weight properties are essential.
Magnetic, electrical, catalytic or non-linear optical properties, ionic transport, redox reversible properties, photoeffects and other physical properties need to be explored in these systems in which the polymeric structure affords an important property: processability.

However, production experiences have shown that the drawing properties of cold sheets rolled with CSP bands are not as good as those of cold sheets rolled from conventional hot strips.
Therefore, in recent years a number of studies have been made on how to produce acceptable hot bands for drawable cold sheet rolling[1-2] .The formability of cold sheets is primarily dependent on their strength level, work hardening ability, morphology of the microstructure and plastic anisotropy..In most cases, these properties are dominated by the grain size and the crystallographic texture resulting from the final treatment in the batch or continuous annealing furnace[3-6].The ability to control these structures through the manufacturing process of the steel is evidently of great importance.
The present paper discusses first the most significant factors that are recognised as affecting the recrystallization microtexture evolution in cold sheet with CSP bands.
Fig1 The annealing technology of the cold rolled specimens The samples for EBSD were mechanically polished and then electropolished in a solution of 400 ml glacial carbinol and 100ml perchloric acid at -30and at 15 V DC for 45-60s, in order to remove the deformation layer introduced during previous mechanical polishing.

It was reported [3-5] that cutting fluid can improve the lubrication properties at high temperature and pressure and, reduce tool bond, improve tool life and get good surface quality.
These alloy elements can improve the mechanical properties, but reduce the machinability.
According to Eqs. 4 and 5, It can be seen that the influence degree of each factor on cutting force as follows: ap>fz>v, for both conditions of dry cutting and wet cutting.
The importance affecting the surface roughness ranks as fz >v >ap for dry cutting.
Due to the cooling and lubrication of the cutting fluid, the build-up edge is difficult to shape, which is an important factor on surface roughness.

This is because a variety of factors influence the cutting process, e.g. material properties, relative die clearance and cutting edge geometry.
The achievable ratio depends on factors such as the diameter, the material properties, the present state of stress and the quality of the pre-cut hole.
Table 1 and Table 2 contain details of the mechanical properties and chemical composition of the test material.
However, test pieces were also manufactured and tested for hole expansion testing in order to achieve wider acceptance of trimming results. 3.5 Determination of the surface properties For the examination of the surface properties the cross sections are measured by means of a digital microscope.
The fundamental procedure for the determination of the generated surface properties is represented in figure 5.

Currently, the methods of improving fatigue properties of welded joints include hammering, shot peening, dressing, and ultrasonic impacting method [4].
Due to the advantages of easier inspection and quality control, flexible operation, no noise, etc., the TIG dressing for welded toe is one of the most simple and effective post-weld treatment process to improve the fatigue properties of joints.
Assuming the cold and heat source move with the same speed v, the shape of the cold source affecting on the specimen plane is oval-shaped, its energy distribution is similar to Gaussian distribution, then in time t ,the cold flow intensity of any point on weld is: qLB = qLexp{-kL[(x-vt)2+y2]} =qLFL(x,y,t) (3) where kL is the concentration factor of the cold source , FL as a function of time, qLis the maximum cold flow intensity.
Nonlinear material properties of high temperature are taken into consideration during the calculation.
Its mechanical and thermal physical parameters depend on the temperature, in the simulation, The properties parameters that close to and above the melting temperature are obtained by extrapolation [8].

Experimental research on microburrs of high speed drilling of PCB using microdrill Xiaohu Zheng1,a, Zhiqiang Liu1,b, Chengyong Wang2,c, Qinglong An1,d, Ming Chen1,3,e 1School of mechanical engineering, Shanghai Jiaotong University, Dongchuan Road 800, 200240, China 2Guangdong University of Technology, Guangzhou, 510006, China 3The State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, Hangzhou, 310027, China awuxizhengxiaohu@hotmail.com, b99422120@163.com, ccywang@gdut.edu.cn, dqlan@sjtu.edu.cn emchen@sjtu.edu.cn Keywords: microburr, printed circuit board, drilling, high speed, microcutting Abstract.
Burr will seriously affect the interconnection of electronic components and accurate installation.
The factors generated burrs are cutting force, cutting temperature, process parameters, tool geometry, board structure, fixture equipment and so on.
The properties of PCB in this study are listed in table.1.
The Formation and Properties of Machining Burrs.

In the manufacturing process of the SiCp/Al alloy composite, an interface region with different physical properties or chemical properties will formed due to the physical or chemical reactions between the particles and the matrix.
The mechanical performance of the interface has important influence on that of the composite material.
The existed studies have shown that the interfacial property is a key factor which must be considered in the performance studies of the composites[1-3].
With the cohesive zone model, the mechanical properties of the interface layer such as strength, toughness, modulus can be reflected by choice of appropriate parameters[10].
Interfacial effects on mechanical behaviors of short fiber reinforced metal matrix composite.