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Microstructure evolution in sintering of alumina–zirconia ceramics simulated by a modified phase field method Chengyang Wei1,a and Saiyi Li2,b 1School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640, China 2School of Materials Science and Engineering, Central South University, Changsha 410083, China awcyxhl@gmail.com, bsaiyi@mail.csu.edu.cn Keywords: Sintering; Phase field method; Grain growth; Densification Abstract.
Although substantial researches have been conducted on optimizing the processing conditions to reduce grain size and porosity and thus to obtain favorable properties in the sintered ceramics [5-8], experimental studies alone are insufficient to gain real-time information about the microstructure evolution in the different stages (e.g. initial, intermediate, and final stages [1]).
It is also noted that the relative green density affects not only the average grain size but also the distribution of the grain size in the ceramics [14].
Overall, these two factors have more apparent effects on the grain size than on the densification.

The impeller is an important component of the centrifugal fan, and its structure directly affects the performance of the fan.
Define material properties of the impeller according to the known conditions, and set the appropriate units.
And the maximum stress is much smaller than the allowable stress ([] =67MPa, allowable stress = yield limit / safety factor, a safety factor of 3.5), meeting the strength requirements.
In the Mechanical of ANSYS Workbench, there are two solvers, namely iterative and direct.

Mechanical properties of the materials considered for both systems subjected to finite element numerical analysis Materials Modulus of elasticity E [MPa] Poisson’s ratio n Density r [kg/mm3] Austenitic stainless steel 1.93×105 0.31 7.86×10-6 Porous bone 100 0.27 1×10-6 Periosteum 15.3×103 0.28 1.8×10-6 Compact (cortical) bone 17.5×103 0.28 2×10-6 The discretization stage was followed by a stage of determination of the pressures and strains acting on the whole system.
The most important is the fact that the tissue of the femur is even more affected, mainly around the epiphysis.
The contact pressure between the stump and the cup is a defining factor for prosthesis functioning and wear determination.
Dependence (multiple regression, structural equation modeling) and interdependence (factor analysis, multidimensional scaling) multivariate analysis methods are suggested for the purpose of developing, testing and refining the measuring scale.

Introduction Advanced engineering ceramics with its excellent physical and chemical properties as wear resistance, corrosion resistance, high hardness, and high temperature resistance, has been widely applied in the fields of aviation, aerospace, engineering machinery etc [1].
In aeronautics and astronautics, by the function of multiple factors, mini crack and tiny air holes will affect on the performance of ceramic materials, even cause disastrous consequences.
Known by the first law of thermodynamics, the heat flux generated by the friction of contact surface can be expressed as [12]: (2) Where, γ is friction mechanical energy into heat energy ratio coefficient.

) tunnel structure of shallow overburden, can effectively reduce the line slope and shorten the length of cross-strait terminal; 2) tunnel cross-sectional shape and size selection is flexible and can be adapted to the passage of vehicles and ancillary pipeline clearance requirements; 3) tunnel rigid pipe section and the section between the flexible joint can be adapted to the river bed, all kinds of sea-bed foundation bearing capacity and deformation characteristics; are well suited to rivers strait at the bottom of the soft ground; 4) pipe section pre-construction methods to meet the long section prefabricated waterproof and reliable performance; 5) pipe section pre-engineering, cross-strait terminal construction, underwater foundation trench dredging and foundation backfill and other construction the process can be routine, and scientific construction organization and effective control of the duration, suitable for a shorter duration of the program; 6) during the operation does not affect
Germany and Japan and other countries was further improved on this basis, Germany phoenix company has developed a phoenix water stop (Figure 1(b)), the more superior mechanical properties, even the Netherlands Zeebrufer tunnel Nowd tunnel also used this waterstop.
Floating transport are influenced by the floating distance of transport, channel depth, hydro-meteorological and other factors.

So far, the majority of the studies on porous NiTi SMAs have focused on fabrication methods, microstructures and mechanical properties [1-6], while less on martensitic phase transformation of porous NiTi SMAs [7].
Since the superelasticity of porous NiTi SMAs has an intrinsic correlation with martensitic transformation, and Ni4Ti3 particles in porous NiTi matrix may directly affect the unique superelasticity.
G0=C44=34GPa=34×109 J/m3, M0=1.008×10-26 mol 2/(J·m·s) [13] are chosen as the normalized factors for energy and mobility, respectively.

PbI2 single crystal has captured significant interest due to its unique properties, including wide band gap (Eg=2.32eV), large atomic number (ZPb=82 and ZI=53), high resistivity(ρ>1013Ω⋅cm), density of 6.2 g/cm3 and good chemical stability [2-5].
There are several main factors to affect high quality PbI2 crystal growth.
Under the constant temperature of 500°C, mechanical oscillation was used to make the raw materials mix uniformly and react completely. (3) After reaction, the ampoule was cooled down to room temperature naturally while excess lead precipitated gradually to the bottom of quartz ampoule.

Introduction Many thermomechanical processing methods for developing engineering metallic materials with desired mechanical properties are based on a phenomenon of primary recrystallization.
The change in textures during recrystallization is affected by two major factors: the preferential orientation nucleation of recrystallizing grains and the preferential orientation growth, when the grains with specific orientations are able to form and coarsen.

Artificial Immune Systems with Negative Selection Applied to Health Monitoring of Aeronautical Structures Fernando Parra dos Anjos Lima1, a, Fábio Roberto Chavarette3,b, Adriano dos Santos e Souza1,c, Simone Silva Frutuoso de Souza2,d, Mara Lúcia Martins Lopes3,e 1 Mechanical Engineering Department, Faculty of Engineering of Ilha Solteira (FEIS) 2 Electrical Engineering Department, Faculty of Engineering of Ilha Solteira (FEIS) 3Mathematics Department, Faculty of Engineering of Ilha Solteira (FEIS) UNESP – Univ.Estadual Paulista, Av.
Structural flaws in aircraft may occur as a result of various factors, such as component wear, cracks, loosening of bolted connections, or simply the combination of these elements.
The spatial variation of the parameters affects the main dynamic parameters, such as response functions, resonance frequencies, damping ratio and eigenmodes of the structure [14].
The material properties used are the modulus of elasticity (E = 700 GPa) and the density (γ = 2710 kg/m3).

Research on Optimal Design and Processing of High-Speed Ceramic Ball Bearings without Inner Rings Songhua Lia, Minghao Fengb and Yuhou Wuc, School of Traffic and Mechanical Engineering, Shenyang Jianzhu University, Shenyang 110168, Liaoning, China arick_li2000@163.com, bfengminghao0826@163.com, cwuyh@sjzu.edu.cn Keywords: Ceramic bearings, Optimization design, Ceramic processing Abstract.
Because of the failure mechanism and material properties of ceramic bearings are different from the steel bearing, there are a series of problems to solve about the design and processing of ceramic bearings.
The mainly parameters of bearing internal structure are ceramic ball diameter Db, the number of balls Z, ball center circle diameter Dm, the radius factor of inner groove curvature fi, the radius factor of outer groove curvature fe and the contact angle α.
The contact ellipse area between ceramic ball and channel is large enough, avoiding contact stress is too high to affect the life of the bearing.