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Introduction Metal cutting is a typical thermo-mechanical process which goes together with the occurrence of high strain, high strain rate and instant temperature increasing in an absolutely small region.
The workpiece material is high-strength wrought aluminum alloy 7050- T7451 and its mechanical and physical properties are given in Table1.
Tab. 1 Mechanical and thermal properties of the material Temperature(℃) 20 100 150 200 Density(kg/m3) 2800 2800 2800 2800 Poisson’s ratio 0.33 0.33 0.33 0.33 Young’s modulus(MPa) 71.7 65.3 61.2 57.9 Yield strength(MPa) 512.5 447.8 376.2 321.4 Thermal Expansion (1 0-6/℃) 21.7 23.5 23.9 24.4 Thermal conductivity(w/m.℃) 134.2 145.3 149.8 175.6 Specific heat capacity (J/kg. ℃) 860.1 902.0 968.6 997.8 Tab. 2 Machining parameters Workpiece size 4×1×2.5mm Tool rake angle 15 Tool clearance 8 Tool flank wear 0 cutting edge inclination 30 corner radius 0 Cutting speed 1000m/min Cutting depth 0.45mm Fig. 1 Three-dimensional oblique simulation model Material Constitutive Model.
The coarser and large elements are allocated in the area of the workpiece and tool not affected by the cutting process [5].
The tool corner radius is one of main factors of influence on the cutting forces.

To date, many investigations have focused on the microstructure and mechanical property of ultrafine-grained materials subjected to ECAP, however, the study on corrosion property is relatively rare.
The study on corrosion resistance of ECAP-processed materials is complex and challenging, because the corrosion resistance will be affected by many factors induced by ECAP, including grain size alteration, changes in dislocation density, increased grain boundary density, particle fragmentation, residual stress, development of texture, as well as different electrolytes [23].
In that way, grain size is an important factor for improving corrosion resistance of materials.

As throat size and exit area ratio that is tip angle and expansion section mainly influence the nozzle characteristics [5], three factors are considered in the flow field simulation: throat length, tip angle and expansion section length.
Turbulence model is Spalart-Allmaras model which is a single equation model[6]: (1) In the equation, is relevant to eddy viscosity, the expression of viscous damping factor is and the relationship between χ, and molecular viscosity is.
The influence of the throat length on the nozzle outlet parameters The throat size of the nozzle has great influence on the performance of the nozzle, the area and the length of the throat can affect the outlet characteristics.
References [1] Hill P G,Miyagawa K,Denton J D.Fast and Accurate Inclusion of Steam Properties in Two and Three Dimensional Steam Turbine Flow Calculations.in:Procinstn.Mech.Engers.
,Mechanical Engineering Science,2000,214:903-919

During the production of the low-pressure casting aluminum wheel hub, the head face deformation and axial deformation of the casting blank are always happened due to various factors.
The aluminum wheel is commonly produced by the low-pressure die casting (LPDC) technique for smooth filling, heat-treatable property, high dimension accuracy and internal quality of the cast wheel.
However, during the low pressure casting process, the actual shape of the casting wheel would deviate from the theoretical shape due to various factors such as size of the mold, casting pattern, spraying ash thickness, hot deformation of the blank and heat treatment.
If the axial deformation is beyond tolerance, the size of hole will be inaccurate, and that will affect the overall appearance of the wheel.
Traditionally, the measurement of the deformation is usually static and by traditional handwork which can be easily affected by the adjustment of the tools and human experience, and the accuracy and the reliability is limited.

It is assumed that the initiated cracks will grow at a constant rate (initiation rate, ν1) until conditions are appropriate for the treatment of cracks propagation with fracture mechanics. ν1 statistical properties are determined using expressions given in M-PRAISE, through correlations expressed as a function of the damage parameter D.
- If the stress intensity factor for a crack is negative, the crack will not grow.
The necessary material properties for the initiation and growth of cracks under SCC in AISI 316 NG steel are preselected in this case and introduced in the code.
The maximal time step for the growth of cracks under stress corrosion cracking is limited to 0.1 year, which means that during a long period of operation at steady state, the crack size, the stress intensity factors, and other computations are updated every 0.1 year.
International Review of Mechanical Engineering (I.RE.M.E.), 3(5) (2009) 640-645

A Way to Reduce Machine Cutting Temperature Ziqin Ma1, a, Yanan Chen1,b, Pengfei Zhao1,b, Tong Wang1,b, Chen Peng1,b, Li Sun1,a, Qiang Cheng1,2,c, Jiang Wei2,c 1School of Mechanical Engineering, Dalian Jiaotong University, Dalian, CHINA 2Dalian Locomotive and Rolling Stock Co., Ltd, CNR GROUP, Dalian, CHINA amaziqin@djtu.edu.cn, b1032416818@qq.com, c442698561@qq.com Keywords: Cutting speed, Cutting temperature, Cutting heat, Cooling Abstract.
Table 1 Heat Physical Properties of 45 Steel Table 2 Computed Results Thermal conductivity Density 49.8 7850 Thermal diffusivity heat Specific 486 Cutting speed(m/min) 300 400 500 600 700 800 Cutting temperature(˚C ) Dry cutting 643 762 718 781 843 935 Cutting temperature(˚C ) Wet cutting 623 745 697 769 820 914 Cutting fluid temperature (˚C ) 32 32.5 33 34 35 37 Fig.1Cutting Speed and Cutting Temperature Theory of Dr.
There are many factors which can affect the temperature.
Fundamentals of Mechanical Manufacturing Technology [M].Beijing: China Machine Press, 2005.38~39.
Mechanical Design and Theory Professional, Dalian University of Technology, 2013.

Cube texture ({001}<100>) is a desired final texture in non-oriented electrical steel sheets used as magnetic cores because it contains two easy <100> axes in the sheet plane, which is beneficial to the magnetic properties.
Plane-strain compression (rolling) of the rotated Goss grains produced shear bands within these grains due to their large Taylor factor.
In the deformed <111>//ND grains, numerous shear bands also form due to their high Taylor factor under plane-strain compression.
It is thus shown that the orientations of the crystallites within the shear bands formed within the deformed matrix play an important role in the nucleation and the subsequent grain growth, i.e. affecting the final texture.
The orientations of the crystallites within the shear bands play an important role in the initial nucleation and subsequent grain growth during recrystallization, i.e. affecting the final texture.

It is clarified that the processing conditions affect the deformation behaviors base on the experiments and analysis.
Its chemical composition (mass %) and static mechanical properties are respectively described in Table 1, 2.
The von Mises yield criterion, kinematic hardening law considered mechanical ratchet deformation and Prandtl-Reuss's flow rule were adopted.
An axial displacement is restrained on left end of the twist side, and the Table 2 Static mechanical properties Yield stress σy0 [MPa] Tensile Stress σb [MPa] Young's modulus E [GPa] Elongation percentage δ (%) 503 610 210 20 Table 1 Chemical composition (mass %) C Si Mn P S 18 25 70 14 36 Fig. 1 Forming machine (Scale 1:15) Twist angle applied parts Axial-compressive load applied parts Fig. 2 Concept chart of processing method Cyclic torsional moment Axial compression l0 Die Die Test specimen forced displacement in the circumference direction is given on the same end.
(1) where σ0 = 930 MPa and is a material constant, β = 0.212 and is a cyclic strain hardening factor.

Fig.3: AFO with air chamber The mechanical properties of the polypropylene sheet that use in manufacturing AFO orthosis are listed in table 1.
Abdullah,Mechanical Properties Of Polymer With Different Reinforcement Material Composite That Used For Fabricates Prosthetic Socket, Journal of Mechanical Engineering Research and Developments (JMERD).42(2019)118-123
Peijs, Effects of environmental conditions on mechanical and physical properties of flax fibers, Elsevier, Part A 32.(2001)1105-1115
Pagar,Fiber-Reinforced Polymer Composites: Manufacturing, Properties, and Applications , Polymers.11(2019)1-37
[11] American Society for Testing and Materials International ,Standard Test Method for Tensile Properties of Plastics,D 638, 2000

Anisotropic friction results from anisotropic distribution of the asperities and hollows on the contacting surfaces and/or anisotropy of mechanical properties of materials.
We can see how the anisotropy on the tribological properties and the fretting orientation affect the mentioned contact variables.
(a) (b) (c) Fig. 11: Resulting wear depth distribution after 18000 cycles for: (a) α = 0o, (b) α = 45o and (c) α = 90o.Table 1: Mechanical properties of IM7Carbon/8551 − 7.
The carbon FRP considered is IM7 Carbon/ 8551 − 7, whose mechanical properties can be found in Tab. 1.
(b) Tribological properties principal axes orientation relative to the rolling direction.