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A certain type of general aviation aircraft piston engine with fuel injector has synthetic clearance overrun fault after long time using, causing flight control difficult, and seriously affect the working properties of engine, in the condition of idle state more obvious, easy to cause unsafe events such as engine parking.
Due to the special nature of flight training, hundreds of inexperience training students coarse and fierce manipulation every year, and flight training time is long, take-off and landing are very frequent, aircrafts and fuel injectors put into overload use for a long time, and are based on mechanical transmission way, led the fit clearance between the various parts of the fuel injector to serious overrun.
It can be concluded that the main factors influencing the engine idle operating characteristics is the synthetic clearance between the throttle stop and the idle valve rocker.
Control Method The big fitting clearance and wear out-of-tolerance situation of RSA series fuel injector has become a big hidden danger affecting the safety of flight training.
[4] CHEN Lian, Analysis and Digital Simulation on the Fuzzy Reliability for Interference Fit , Journal of Mechanical Strength, 2007.29

This paper presents new evidence for an interpretation of plasticity-induced crack tip shielding as arising from two separate effects; a compatibility-induced interfacial shear stress at the elastic-plastic interface along the plastic wake of the crack, and a crack surface contact stress which will vary considerably as a function of stress state, load and material properties.
Fig. 1 a) Crack tip stress intensity factors obtained by fitting the mathematical model to full field photoelastic fringe patterns.
The effects of contact length and the back stress are at least partly independent, as notch plasticity leads to curvature of compliance traces even in the absence of a crack, while plastic zone correction factors to crack length are predicated on this basis.
c) Fringe patterns around a growing fatigue crack under an applied stress intensity factor of 1.5 MPa√m.
Fract. (2006) Applied Stress Intensity Factor K (MPam 1/2 ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 Calculated Stress Intensity Factor Keff (MPam1/2 ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 Applied K vs Calculated K

For bending ordinary parts, the parts' curvature and angle have changed because of springback thus affecting the bending precision.
Micro tensile and bending test of pure copper foil Many factors affect metal sheet bending springback, just as blank thickness, grain size, bending angle, radius of die and clearance between punch and die.
Stress-strain relationships obtained in the tensile tests of Section 2.1 are set as materiel's plastic mechanical properties in order to ensure a more objective reality simulation result, Young's modulus E also take the corresponding  values in the stress-strain curves.
Influence of material thickness on bending springback Sheet thickness is an extremely important factor effect on bending springback both to macro and micro forming process.
Foils with thicknesses of 30μm, 50μm, 90μm, 140μm and 190μm are selected, stress-strain relationships obtained by tensile test after annealing(Heating to 400 ℃, holding temperature for two hours) as the materiel’s mechanical properties as numerical simulation are carried out .

Load - deflection curve can be obtained by testing different stirrup ratio of beam based on the test, shown in Figure 1 (a), it can be seen from the figure that the stirrups isn’t the main factors to affect load - deflection curve.
This shows that the stirrup ratio isn’t the main factors to affect Beams reinforced beam stress reinforcement.
Carbon fibers added to the concrete, which can effectively improve the tensile properties of concrete and effect of crack resistance is influenced by many factors.
P.L.Bernburg,E.M.Gartner and A.Bentur.Carbon Fiber Reinforced Cement and Mortar .Proceedings.Materials Research Society,Pittsburgh.PA.211.255 [5]H.L.Cox.The Elastricity and Strength of Paper Other Fibrous Materials.British Journal of Applied Physics.1952.3.72 [6]K.Nishioka,S.Yamakawa,K.Shirakwa,Properties and Applications of Carbon Fiber Reinforced Cement Composites.Development in Fiber Reinforced Cement and Concrete,RILEM,Symposium,Sheffield,1986
[9]Ni Donggao, Lu Liyan, Liu Guiping.The Analysis on the Factors Affecting the Tensile Strength of Carbon Fiber Reinforced Concrete [J].

Recent studies [5-10] have shown that fracture toughness can be strongly affected by specimen size, crack depth and loading configuration.
Volumetric Method, presented by Pluvinage [11] is a meso-mechanical approach belonging to this NFM.
Material properties and Finite Element Modelling The material used in this study is an X52 steels meeting requirements of API 5L standard.
Table 1: Chemical composition of specimens material (weight %) C Mn P Si Cr Ni Mo S Cu Ti Nb Al 0.22 1.220 - 0.240 0.16 0.14 0.06 0.036 0.19 0.04 <0.05 0.032 Ref[12 ] 0.15 1.250 0.025 0.350 - - - - - - - - In Table 2, mechanical properties of API X52 are presented.
Table 2: Mechanical properties of API X52 E (GPA) y (MPa) u (MPa) A% n k K Charpy Energy (J/mm 2) 210 410 528 32 0.164 876 116.6 - Ref[12] in longitudinal sense 210 493 623 30 - - - ~ 75 Ref[12] in circumferential sense 210 410 638 19 - - - 22 The pipe geometry of this study is a cylinder with a V-shaped longitudinal surface notch subject to different internal pressure P as shown in Table 2.

However, these materials often have poor mechanical properties and varied properties and degrade rapidly.
In addition, the physicochemical property of the material surface is also an important factor closely related to the behavior of cells.
Because the cell growth is affected by mechanical forces and chemical substances, which subsequently affecting the formation of cartilage, addition of signal factors or growth factors to synthetic materials can promote the formation of tissue-engineered cartilage both in vivo and in vitro.
Nanostructure scaffolds have good mechanical properties, that match with cartilage biomechanical environment, and maintain the stability and integrity of the structure in the body.
Effects of harvest and selected cartilage repair procedures on physical and biochemical properties of articular cartilage in the canine knee.

SEM images of coating cross sections are presented in Fig. 2, mechanical properties of the coatings are summarized in table 3.
Table 3: Mechanical properties of HVOLF (K2) sprayed coatings.
The stress distribution in the coating/substrate interface is a factor which affects the coating adhesion.
Consequently coating properties are strongly affected by this circumstance.
High Velocity Suspension Flame Spraying of nano oxide (n-Al2O3, n-TiO2/TiC, n-Cr2O3) containing suspensions leads to fine structured coatings with improved mechanical properties.

From the results, tensile properties and hardness of TPVs are slightly affected by processing conditions.
Parameters of mixing and products’ properties will be studied.
Physical Properties Table 1 shows physical properties of TPVs.
However, we found that the mixing pattern has slight effects on mechanical properties of TPVs.
Soares, The Effect of Mercapto- and Thioacetate-Modified EPDM on The Curing Parameters and Mechanical Properties of Natural Rubber/EPDM blends, Eur.

Polymer nanocomposites are a class of materials that combine electrical, thermal, dielectric, magnetic and/ or mechanical properties, which are useful for the suppression of electromagnetic interference.
In a nanocomposite, fillers are nanometrics and show large interfacial area per volume, which leads to significant changes in their properties [1] such as electrical and electromagnetic properties that are required for EMI shielding.
These results can be improved by adding a magnetic phase such Cobalt to reinforce the magnetic properties of the slabs.
Summary In this work, we reported on the structural and electromagnetic properties of nanostructured Cu powders by high- energy mechanical milling process.
Shi, ‘’Effects of nanoparticles on the thermal and mechanical properties of epoxy coatings’’, Journal of Nanoscience and Nanotechology, vol.16(2016) pp.9874-9881

Introduction Single crystal silicon are the important substrate materials of integrated circuits and TR optical materials because of its choiceness properties, such as high mechanical strength, steady chemical property, high refractive index, few dispersion and good optical constants[1].
And the actual value of roughness is determined by the properties of silicon.
Table 1 The orthogonal experimental scheme L25(53) factors ap f n levels （） （mm/min） （r/min） 1 1 1 4000 2 2 2 5000 3 3 3 6000 4 4 4 7000 5 5 5 8000 Fig.4 The site of presetting cutter The detection of the experimental results.
And the influence factors of the roughness include R, f, n and ap.
Wu: China Mechanical Engineering, Vol. 25(2014)No. 3, pp. 290-294.