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The mechanical properties of thermal spray coatings are dependent on pore and microcrack content, particle size, and the percentage and distribution of the phases that are present.
The excellent bone connection to HA coatings, allied with good substrate mechanical properties, gives the implants sufficient strength for excellent performance in cases that require high structural strength to support high loads and/or applications needing rapid implant bioadhesion [1].
Hydroxyapatite is a ceramic material, and to better understand its mechanical properties when used in real medical applications, fracture mechanics must be utilized.
These factors have provided the incentive for studies to evaluate the possibility of using the scratch test in the evaluation of thick ceramic and polymeric coatings produced by thermal spray process [5, 6 and 7].
Holmberg, K. and Matthews, A., "Coatings Tribology Properties, Techniques and Applications in Surface Engineering", Tribology series 28, Elsevier, Amsterdam London New York Tokyo, (1994). 12.

Their properties are suitable for reformed aggregate of ordinary Portland cement.
Both low calcium and high calcium fly ash geopolymers possess good engineering properties [6-10].
Influencing factors on the drying shrinkage The data of drying shrinkage strains of high calcium fly ash geopolymer pastes versus sodium silicate to sodium hydroxide ratio are plotted in Fig. 2.
-Effect of sodium silicate to sodium hydroxide ratio The results clearly showed that the drying shrinkage deformation was affected by the ratio of sodium silicate to sodium hydroxide ratio.
Conclusions From the results of the study, the following conclusions can be made. 1) The parameters affecting the drying shrinkage of high calcium fly ash geopolymer are weight ratio of fly ash to alkali solution, sodium silicate to sodium hydroxide ratio and concentration of sodium hydroxide. 2) The drying shrinkage deformation of high calcium fly ash geopolymer decreased with a decrease of sodium hydroxide concentration and increase of fly ash to alkali ratio.

FEM Analysis of Sheet Incremental Forming Process Liu Jie School of Mechanical & Electrical Engineering, Shenzhen Polytechnic, Shenzhen, China liujie@szpt.edu.cn Keywords: sheet incremental forming, dieless forming, FEM.
FEM SIMULATION OF THE FORMING PROCESS As the sheet metal layered plastic forming process is rather complicated and the parameters and tracks is difficult to be selected by trial process, how to choose feasible parameters is the key factor for an ideal workpiece.
Unlike the traditional prototype of single cycle pulling forming, the layered plastic forming prototype simulates the layer forming process on the basis of the material property.
Factors affecting the quality of workpiece are very complicated.
References [1] Yoon SJ and Yang DY, Investigation into a new incremental forming process using an adjustable punch set for the manufacture of a doubly curved sheet metal, Proceedings of the Institution of Mechanical Engineers Part B, Journal of Engineering Manufacture, Vol.215, Issue 7, pp.991-1004, 2001

Research on Advance Control of Chaotic Vibration Machine with High Vibration Intensity (Ⅰ ) ----- Mechanical Properties and PLC Control Decision Xiaolan Yang1, 2 a, Jifeng Liu1, 2，Hansong Yang2, Bingzhi Kong1, Jiawei Li1 and Mengnan Si1 1Nanjing Institute of Technology, Nanjing, Jiangsu, 211167, China 2College of Engineering，Huanghe S & T University, Zhenzhou 450015 ayxhh001@163.com Keywords: High vibration intensity, Chaotic vibration, Vibration machine, Advance control, Intelligent frequency conversion Abstract.
Analysis of Mechanical Properties and Control Ideas Analysis of Mechanical Characteristics.
According to equation (2), we can know the complex motion of such a mill system, due to the system is affected of the frequency conversion, collision, impact and vibration, the state of strong nonlinear vibration or chaotic vibration with certain excitation and uncertain response are appeared usually.
through the advance control software, control signals are transferred to the inverter by PLC, the frequency conversion control of the vibration mill can be achieved, on the other hand, PLC continues to receive the detection signals from the sensor transfer, and through its integral amplifier and calculator, parameters such as vibration intensity are transmitted to the advance control software; Selected inverter has a built-in PID controller, its function parameter set can define upper and lower limits of external input signals; As the frequency setting signals, the inverter allows the analog voltage or analog current input signal, and use the differences between the target signal and the feedback signal to adjust the output frequency, in this way, not only regulation accuracy can be contented but also the output frequency can be adjusted with a certain sensitivity; the output voltage of controller can be expressed as: Where, : input deviation, : given value, : measured value, :scale factor
References [1] Jifeng Liu, Xiaolan Yang, Jinchao Zou: Journal of mechanical engineering, Vol.44 (2008), p190

Finally the forged product is then heat-treated to improve the mechanical properties.
The finished products have the following mechanical properties: Rp0,2 > 300 MPa, Rm > 340 MPa, A5 > 10 %.
The type of the material, the state of its microstructure, its casting and forging properties are defining factors.
Increasing the silicon surplus alters the mechanical properties; especially the elongation can be negatively affected.
Afterwards the microstructure and the mechanical properties of the cast-forged material were analyzed.

Structure noise of marine gearbox seriously affects warship’s concealment, stability of transmission system and amenity of crew working environment.
(a) Geometric model (b) Grid model (c) Finite element model boundary conditions Fig.1 Box model Determine unit types and material properties.
After meshing in HyperMesh, set material properties, designate materials of planetary reduction gear box alloy steel according to provided information.
The specific material parameters are on the basis of mechanical design manual, which is Q235.In order to prevent too great a variation of amplitude in harmonic analysis resonance conditions, considering the material loss factor of Q235, the material properties are as shown in Table 1.
Table 1 Material properties of planetary reduction gear box Material Elastic Modulus (MPa) Poisson’s ratio Density (t/mm3) limit of yielding intensity (MPa) loss factor Q235 2.0e5 0.3 7.8e-9 235 2e-4 Modal Analysis of Reduction Gear Box.

Optical communication with its high speed, wide band, large capacity, low loss and other advantages, has become one of the most important factors of traffic growth.
To a certain extent, affected the reliability of optical fiber connector, optical transmission system and the performance.
Because the ceramic materials and quartz fiber thermal compatibility good, stable physical and chemical properties, therefore, the main development of the industry with the diameter of 2.5mm ceramic fiber connector ferrule as the core device.
The mechanical system is consisted four parts.
Imported linear guide rail assure the mechanical system runs in high precision and more stability.

Various parameters that affect the machining processes were identified and a consensus was reached regarding its values.
Introduction Titanium and its alloys has played a significant role in the field of aerospace, energy, chemical and bio-medics due to its high strength to weight ratio and exceptional mechanical and chemical properties.
Feed four factors considered for the experiment.
For a 4 factor 3 level experiment more than 80 experiment have to be carried out leading to a very huge expenditure and waste of time.
Ghani ,International Journal of Mechanical and Materials Engineering (IJMME), Vol. 4 (2009), No. 2, 191-196 [2] X.Yang, C.R.

Electromagnetic stirring is an effective technique of improving the solidification structure and mechanical properties during continuous casting，because there is a notably effect of the flow on the density,segregation and inclusion of molten metal.
So, electromagnetic stirring is an effective technique of improving the solidification structure and mechanical properties[1~5].
The research results is helpful to optimize the processing parameters for acquiring the billet with better mechanical properties.
As well, several factors will affect the measurement accuracy such as the number of little coil, the magnetic field and the artificial operation.
Microstructure and mechanical properties of semi-solid ZL101A alloy prepared by EMS-DC method[J].

Principal chemical composition and distribution of hybrids particles are important factors controlling the properties behavior.
The addition of reinforcements with proper selection phases in metals matrix alters and improves their mechanical and physical properties.
It has been found that alumina reinforcement improves the mechanical and physcial properties of the composites [1-4, 9-11].
GU, Mechanical Properties and Damping Capacityy of (SiCp+ Al2O3.Sio2f/Mg Hybrids Metal Matrrix Composites, Journal of Alloys and Compounds, Vol. 383, (2004), P. 104
Ray, Effect of porosity and Alumina Content on the Mechanical Properties of Compocast Aluminium Alloy-Alumina Particulate Composite.