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The operational ability of traditional ripper is affected by factors of machine heavy, adhesion coefficient and soil condition of the construction site, the engine’s power cannot make full use of because of track skid.
Gear lever belongs to unidirectional bending member, its strength is calculated taking into account safety factors and the influence of initial defects of components, the additional bending moment caused by initial defects (such as initial deflection ) is included in the basic bending moment.
The maximum stress of ripper occurs in section A in the direction from the tip along the rod at 700 mm, the section properties are shown in table 1.
Mechanical analysis.
And the traction considering dynamic load factor is called the calculated traction, calculated according to formula (12): (12) Where: －dynamic factor, when the ripping speed is,ripper tooth lifting speed , according to the following scope to choose: Horizontal resistance generally takes; When the vertical resistance makes a bulldozer instability,; When considering the lateral force,.

The authors thought that the reduction of friction coefficient and achievement of a good, durable performance of MWCNTs coating were contributed to three factors as follows: (1) Friction resistance is minimized by rolling motion of the cut or broken MWCNTs and the short graphene lamellae in the wear track
Ultra-low friction was therefore obtained due to their well-known lubricating properties.
Fortunately, some other researches did fundamental experiments on tribological properties of CaCO3 nanopartiles.
[10] H.O.Pierson, Handbook of carbon, graphite, diamond and fullerenes: properties, and applications, Park Ridge, NJ: Noyes Publications, 1993
[18] M.F.Yu, B.S.Files, S.Aprepalli and R.S.Ruoff, Tensile loading of ropes of single wall carbon nanotubes and their mechanical properties, Phys.Rev.Lett. 84(2000)5552-5555

The creep of alloy is affected by factors such as stress, temperature and time [2].
Therefore, it is necessary to make relevant research on these factors.
Tensile properties at ambient temperature and its service temperature, thermal stabilities, oxidation properties, creep properties at 600℃[2], and fatigue properties[1] of the alloy have widely been studied by several researchers.
And the alloy has the potential to be used at 650℃, it is necessary to investigate the mechanical properties for the alloy, especially for the creep at 650℃, so that the application for the alloy can be enlarged.
Guo, Tensile and creep properties of Ti-600 alloy, Trans Nonferrous Metals Soc China. 17 (2007) s522-s525

Additionally, photoluminescence (PL) spectra were measured at room temperature, besides the Ge contents of the SiCGe layers, the film defects were also found to affect the curve shape, peak postion and the full width at half maximum (FWHM) of the photoluminescence results.
To begin a CVD growth, the substrates were treated in H2 circumstance at 1250℃ for 10 min to remove the crystal damage causing by the mechanical polishing process.
SEM and TEM tests showed that the growth temperature was a main factor affects the surface morphology, island component and crystal structure, and the SiCGe samples had layer-by-layer growth mode at 1250 oC.
Additionally, besides the Ge contents of the SiCGe layers, the film defects were also found to affect the curve shape, peak postion and FWHM of the room temperature photoluminescence results.
Tauc: Optical Properties of Solids (North-Holland, Amsterdam 1972, p. 372) [9] C.F.

In addition, residual stress was also studied since it was a main factor of failure and performance of structural in engineering application.
From Fig. 5 (b) and (c), the surface integrity of EDM surface layer was presented white layer, heat affected zone and parent material.
The crater, white layer thickness, heat affect zone and martensite can be found from observation by optical microphotographs.
Sakaguchi: Tribological properties of dimple silicon nitride under oil lubrication, Journal of the European ceramics Society, Vol.24 (2004), pp.369-373
Uehara: Micro-texturing technology for friction-control-surface, The Japan Society of Mechanical Engineers, Vol.06-34, pp.269-270

Several studies concerning ferrite grain refinement have been developed in recent the last years due to the recognised influence of such microstructures on steels properties.
This work was focused on the evaluation of the microstructure and mechanical properties of an ultrafine grained CMn steel obtained by hot torsion deformation and intercritical annealing.
Hence, the only major factor affecting the value of the stress would be the relative volume fractions of austenite, ferrite and cementite present at the soaking temperatures, previous to straining.

The details of thermo-mechanical processing regime took in this work are displayed schematically in Fig. 1a.
The contact interfaces between the billet and dies was set as shear type, and friction factor was taken to be 0.15 due to the water-based-graphite lubrication.
The forging flow lines could induce anisotropy in the mechanical properties [11].
The mechanical properties of the product were influenced by the flow lines.
The flow lines should be arranged in parallel to the working surface; on the other hand, if there were disordered through the flow lines, the mechanical properties will be affected [12].

FEM and Contour Method Study of Quenching Residual Stress of 7050 Aluminum Alloy Cross-Shaped Component Yang LI1,2,3,a, Yunxin WU1,2,3,b*, Hai GONG1,2,3,c and Feng XIAO1,2,3,d 1State Key Laboratory of High Performance Complex Manufacturing, Central South University,  Changsha 10083, China 2School of Mechanical and Electrical Engineering, Central South University, Changsha, China 3Nonferrous Metal Oriented Advanced Structural Materials and Manufacturing Cooperative  Innovation Center, Central South University, Changsha 410083, China aliyangcsu12@163.com, bwuyunxin@csu.edu.cn, cgonghai@csu.edu.cn, drock03_25@163.com Keywords: 7050 aluminum alloy; Cross-shaped component; Quenching residual stress; FE analysis; Contour method Abstract: In order to study the quenching residual stress of typical aluminum alloy component used in aerospace, the finite element (FE) model of quenching process of 7050 aluminum alloy cross-shaped component was established based on heat transfer theory and
Introduction During the quenching process of aluminum alloy components used in aerospace, high residual stresses are introduced [1], the high residual stresses will hamper the alloy’s favorable mechanical properties maintaining and hamper the shape maintaining in the subsequent processing.
Contour Method can measure the distribution of residual stress field of cutting surface and not affected by the thickness and organization of the specimen.
Ignore the phase change factors, the latent heat of phase change is zero in formula (1).
It can be seen from the figure 3 and figure 4, the distribution of longitudinal stress is more complex at connect parts of the rib and the web, and there is larger tensile stress concentration at “a” area in figure 3, take left margin of cross-shaped component as a starting point, the affect region reach to the 112.5mm.

Dynamic Analysis Based On ANSYS of Turning and Grinding Compound Machine Spindle Box Zanhui Shu and Qiushi Han School of Mechanical and Electrical Engineering, Beijing Information Science & Technology University, Beijing, China E-mail: shuzanhui2006@163.com Keywords: FEM; dynamic characteristics; modal analysis; harmonic response analysis Abstract.
The performance of high-speed machine tools is affected by the dynamic characteristic of machine tools in the very great degree.
Fig.1 Structure of machine tools Fig.2 Spindle box of machine tools Fig.3 Spindle box 3d model and finite element mesh model The spindle box of the three-dimensional entity modeling is established using Pro/e software in this paper, shown as Fig.3.Determining the number of classification finite element is the key factors of establishing finite element model. to one of, relationship to solving the computation The precision speed and expenses etc of calculation are related to the units quantity.
Because the intensity and rigidity were affected by spindle hole much, spindle hole and spindle box were considered together when modeling.
[5] LiuXiuLian,”CNC machine tool spindle dynamic stiffness properties of study and test”, Coal Mine Machinery,2008,29 (7)

The time-domain measurement method of torsion pendulum of moment of inertia is affected by period measuring precision; when torsion pendulum motion is affected by air damping and other outside interferences, the cycle of torsion pendulum motion is not stable any more; the measurement precision of moment of inertia is affected finally.
There is mapping from un-damped natural vibration frequency [ωn(i)] and bandwidth [fw(j)] to damping ratio [ζ(k)]; (4)It is also closely related between damping ratio ζ and sampling rate fs, sampling point N, fs and N affects the metric of frequency bandwidth by influencing frequency resolution of spectrum analysis.
The measurement results of moment of inertia of sample parts based on FFT method Sample partⅠand Frock Sample part II and Frock f0 (Hz) JFFT (kg·m2) JT(kg·m2) f0 (Hz) JFFT (kg·m2) JT(kg·m2) 1 0.2857 144.0714±12.0060 146.7639 0.3095 122.7589±9.4430 124.1039 2 0.2857 144.0714±12.0060 146.7639 0.3095 122.7589±9.4430 124.1039 3 0.2857 144.0714±12.0060 146.7639 0.3095 122.7589±9.4430 124.1039 4 0.2857 144.0714±12.0060 146.7639 0.3095 122.7589±9.4430 124.1039 5 0.2857 144.0714±12.0060 146.7639 0.3095 122.7589±9.4430 124.1039 In Table 1, the measurement uncertainty part of results is contributed by frequency resolution and ignores other factors.
Mu, Analysis of Measuring System and the Error of Missile Moment of Inertia based on the torsion pendulum method, Mechanical Engineering and Automation, Vol. 1(2009), pp.103-104
[5] Richard Boynton, How to Calculate Mass Properties.