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In the following, the high temperature properties are studied systematically [26, 27].
Although langasite family resonators can be excited piezoelectrically up to temperatures close to their melting point, some factors limit their practical use at high temperatures.
In this case the Qf reflects the materials properties for a given crystal.
Sitar, The growth and optical properties of large, high-quality AlN single crystals, J.
Fukuda, High temperature properties of langasite, Mater.

All ensure the required tightness, mechanical strength and microstructure of the joints.
Materials based on intermetallic compounds of nickel and iron with aluminium show unique mechanical properties as well as highstability at elevated temperatures.
This may be attributed to a change of the properties of the steel as a result of its becoming plastic [8] and carburized (graphite moulds) at these temperatures.
When produced under adequate thermodynamic conditions, the NiAl phase was the only constituent of the interlayer; • In joining ceramics with metals by the reactive sintering of intermetallic compounds, it is important that the joining process parameters should be carefully selected so as to take into account the factors that affect the formation of the intermetallic compound (e.g., the stoichiometry of the chemical composition, process temperature) as well as the factors specific for joining these two materials (e.g., temperature, joining time, heating and cooling rates).
This work has been supported by State Comittee for Scientific Research (Poland) under grant No 3 T08D 028 26 References [1] Weise W., Malikowski W., Krappitz H.: Wetting and strength properties of ceramics to metal joints depending on brazing conditions and joints geometry.

Based on the properties of the orthogonal polynomials, a Fourier neural network can be established, which is a feed-forward network consisting of three layers, that is, input layer, single hidden layer and output layer, as shown in Fig. 1.
The reliability probabilistic constraints are imposed in order to take into account various random parameters which affect the reliability of the structure.
When the reliability index is calculated, the variables which affect the reliability of the structure are considered as the inputs of the neural network, and the performance function is taken as the outputs of the network, thus the neural network can be established.
Table 2 Optimum results for the five-bar truss compared with RBDO method Proposed method RBDO method Cross-sections at the optimum (mm2) A1 613.473 613.499 A2 200 200 A3 613.473 613.499 A4 200 200 A5 200 200 -value at the optimum 3.0000 3.000 Cost function value (mm3) 1.9926×106 1.9927×106 Conclusions The deterministic optimum cannot be considered as a realistic optimum design since the random factors affect the structures.
Marti: Reliability-based design optimization for elastoplastic mechanical structures.

Inconel 718, a nickel-based superalloy, features a high complex of properties owing to solid solution and dispersion strengthening mechanisms.
This work does not include the study of the way heat treatment affects the phase composition and properties, so the results refer to the products manufactured using SLM without further heat treatment.
The results of the tests showed that the mechanical properties are comparable to the properties of the specimens manufactured by the casting technology before heat treatment: σ0.2 = 477 MPa, σu = 752 MPa, δ = 33.8% [15].
The ability to control the trajectory of the laser allows using this technology for creating products with anisotropic properties in future.
The microstructure and mechanical properties of deposited-IN718 by selective laser melting, J.

Compared with the properties of other structural alloys based on iron and aluminum, a distinctive feature of this class of non-ferrous metals is the difference in the level of physical and mechanical properties.
On the other hand, the particular physical and mechanical properties of titanium Ti alloys adversely affect the technological properties in the manufacture of critical products.
Besides, these factors can reduce the operational ability as a result of the formation of defects on the surface of the manufactured product [1–4].
This fact is confirmed by experimental studies to determine the mechanical properties for a standard Ti-4.5Al-2V sample (Fig. 2a) and with a local inhomogeneous structure (Fig. 2b).
In this case, the critical point remains to take into account the mechanical properties of the local inhomogeneous structure, extended to a depth tc=0.02 mm.

Ultrasonic lapping is the processing method compounded of mechanical lapping and ultrasonic vibration.
The properties of test materials are listed in Table 2.
Test Results and Analysis During the lapping, lapping parameters can change the trajectory of abrasive and can affect the brittle-plastic removal mechanism of material, which change the value of material removal rate.
A study of the material removal properties in ultrasonic lapping of ZTA ceramics with fixed abrasives by using an online acoustic emission monitoring system [J].
Study on the Theoretic Model of Ultrasonic Polishing[J].China Mechanical Engineering, 2005,16(8):664-666

Introduction The materials made the braced pillar of vacuum plate glass may be non-rust steel, tungsten carbide steel, chrome steel, aluminum, nickel, molybdenum, tantalum, ceramics, etc [1]. 10Ni3MnCuAl steel belongs to low carbon medium alloy precipitation-hardening steel and has high hardenability, fine complex mechanical properties, mirror machining property, EDM Performance, pattern sculpturing performance and welding performance after heat treatment. 10Ni3MnCuAl steel was adequate for producing braced pillar.
The coefficient of thermal conductivity is increased and the transparency of glass is affected when the contact area between the braced pillar and glass is oversize.
It showed that the residual stress and permanent stress of glass was the factor of reducing life period.
It showed that the residual stress and permanent stress of glass was the factor of reducing life period.
It will directly affect service life of the vacuum plate glass.

From taguchi factor effect diagram it has been found that pyrolysis temperature and silica source plays major role in improving the yield. 1.Introduction SiC has always been noted for its excellent mechanical properties, specifically, hardness and wear resistance.
Important stage in the design of experiment is the selection of factors and levels Significant factors that affect the silicon carbide yield are selected based on literature survey and experience. 4 factors at 3 different levels are chosen and the variables are heating rate, pyrolysis temperature, and silica source and silica content.
Table 1.Design of experiment – Factors and levels Factors Level 1 Level 2 Level 3 Temperature [C ] 1400 1600 1800 Silica source colloidal silica sodium silicate quartz Heating rate [°C/min] 5°C 10°C 20°C Silica content [wt%] 10 20 30 Analysis of signal to noise (S/N) ratio is needed to evaluate the experimental results.
Results and discussion The experiments were conducted with an aim of relating the influence of silica source, pyrolysis temperature, silica content and heating rate on silicon carbide yield.On conducting the experiments as per the orthogonal array, results were obtained and factor effect diagram is drawn for each factors.
Figure 1 shows the factor effect diagram of Taguchi’s signal to noise ratio for SiC yield.

Machining of these materials with the use of traditional machining techniques are becoming difficult task, because, of its high strength, stiffness, high hardness properties.
The concept of orthogonal array of experiments in Taguchi method useful to determine the factors which most affect product quality with a minimum number of experiments, thus saving time and resources [13].
The experimental runs have been conducted on WEDM using L16 orthogonal array of Taguchi method with four factors four levels each.
The parameter wire feed (B) do not affecting surface roughness at 95% confidence levels as its P value if more than 0.05.
From the AS/N table, it is found that voltage gap (A), pulse on time (C) and pulse off time (D) are significant factors for surface roughness b.

A study on the coating of acupuncture needle with bioceramics to improve insulation performance Man Tae Kim 1,a , Hyup Jae Chung 2,b , Gyu-Seok Choi 1,c Yong Bae Kim 1,d and Kyong Yop Rhee3,e 1 Gumi Electronics & Information Technology Research Institute, Gumi, Korea, 730-853 2 Graduate School of Mechanical Engineering KyungHee University, Yongin, Korea, 449-701 3 Industrial Liaison Research Institute, Department of Mechanical Engineering, College of Engineering, KyungHee University, Yongin, Korea, 449-701 a giggiscan@naver.com, bjhj819@paran.com, cgschoi@geri.re.kr, dybk@geri.re.kr e rheeky@khu.ac.kr Keywords: Acupuncture needle, Insulation, Bioceramic, Plasma spray Abstract.
The results also showed that the heat conduction of heat-acupuncture needle was significantly affected by the bioceramic coating on the needle.
The heat-acupuncture therapy, which is applied heat by heat source, affects autonomic nerve and secretion, which strengthens the immunity system of body.
The thermal properties of silver and coating materials used in this study are represented in Table.1.
(a) Case 1 (b) Case 2 (c) Case 3 Fig. 3 SEM image of needle surface of three cases The condition of coated surface is an important factor in the coating quality.