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For accurate measurement of the dynamic fracture properties, we need to thoroughly understand the contact situation of the three-point bend specimen, with the loading apparatus.
Introduction The robust design of structures under dynamic loading requires material’s dynamic fracture properties to be included.
At present, Hopkinson pressure bar apparatus with different arrangements is used for measurement of material’s dynamic fracture properties.
According to experimental work of Guo et al. [5, 6] the dimension of the specimen and span are important factors that affect specimen’s contact state during loading.
Linear-elastic behavior is considered for the model, with material’s mechanical properties as, Modulus of elasticity: E =210 GPa. , Poisson ratio: µ = 0.3 and density: ρ = 7850 Kg/m3.

Physical and mechanical features of SiCp/Al composites, ELID grinding experiment equipment and grinding conditions are as shown in table 1 and 2 respectively.
Table 1 Physical and mechanical properties of SiCp/Al composites Experiment materials Volume fraction Tensile strength /( MPa) Elasticity modulus /(GPa) Elongation （%） SiCp/Al composite materials 40% 441 125 0.7 Table 2 Experiment equipment and grinding conditions Experiment  equipment Machine tool Ultra precision molding surface grinder MSG - 612 CNC (modification) Measuring instrument TR300 surface roughness measuring instrument S - 3400 type N Ⅱ scanning electron microscope Grinding conditions Wheel Copper-iron bond diamond pellets（W40,W10,W5） Lapping liquid Electrolysis Lapping liquid Electrolysis power High frequency DC pulse power[3] Grinding process parameters setting By analyzing the main mechanical properties of SiCp/Al composite materials and similar materials grinding process parameters, combined with grinding characteristics of this material, optimized by grinding process parameters is as shown in table 3.Thus the machined surface roughness can obtain Ra0.030μm and
(2) High quality of the workpiece is formed by the comprehensive factors influencing each other, not only the pursuit of a single grinding parameters change, but also considers the combination of different grinding process parameters.
(3) The grinding depth, grinding wheel rotation speed and feed speed are the main factors to affect the surface quality.
Journal of Mechanical Engineering, 2000, 36(5): 89-92 .In Chinese

The influence factors on the density uniformity of SiCp/2024Al in the extrusion process were studied in the present investigation.
Those factors contain the extrusion ratio, the extrusion velocity, the temperature and the friction coefficient.
Those factors are all lead to the difficulty of the extrusion process[5].
[4] GEIGER A L, WALKER J A, The processing and properties of discontinuously reinforced aluminum composites.
Effect of extrusion ratio on the microstructure, texture, and mechanical properties of(Mg/AZ91)m–SiCp composite, Materials Science & Engineering A . 624(2015) 279-290

If analyzed by artificial neural network technology[4～6], material fatigue damage affected by various factors is unstable, and the relation among transient damage, material property and load stress is complicated and nonlinear mapping.
Fatigue design also tends to develop based on the original design, accumulating data, considering the real complex conditions such as structures interacting, stress concentration factors considered, load model influence and material property parameters under stress conditions, etc. for the application and simulation of reliability design.
Safety factors 2 and 20 are selected respectively on the basis of theoretical stress amplitude and cycle index, the lower of which is used to design the fatigue curve and its curve cycle index N is 10～105 cycles.
Frequency of operation and shutdown is mostly regarded as cycle index of design calculation standards without consideration of environmental factors.
Because of computation factors the sudden natural loads have long been simplified greatly leading to rough results, and disastrous accidents occur frequently.

In operation, rotor is mainly affected by tension, compression, bending and torsion.
The main failure mode is fatigue failure, and may also be affected by stress corrosion cracking, plastic deformation, and other forms of failure.
There are lots of studies and research on these topics, which are mainly in the low-cycle fatigue properties of turbine generator rotor structure and materials, high-temperature creep, fatigue, fracture toughness.
When the constraint is applied, based on the symmetry properties of the rotor structure, the use of polar coordinates, the symmetry constraint is applied in the plane of symmetry of the structure, the wedge pressure of the coil and the insulating member is applied in the bottom of the wedge.
Table 1 The rotor maximum stress and safety factors of different units Unit type n(r/min) Tooth head maximum stress Tooth head minimum safety factor Maximum stress of the wedge Minimum factor of safety of the wedge Flat 3000 427.67 1.61 138.88 2.27 Flat 3600 615.84 1.12 199.99 1.58 Entity 3000 415.54 1.66 101.21 3.11 Entity 3600 598.38 1.15 145.74 2.16 As can be seen by Table 2, the plane unit and the physical unit can be used to check out of stress of the rotor teeth head and the wedge portion.

Introduction Carbon nanotubes have been widely used to reinforced composites due to their superior mechanical properties, such as its high elastic modulus, strength, and toughness etc [1,2].
The difference of interfacial mechanical characteristics can lead to a great change of the composite properties, which can be the main factors for the mechanical behaviors of materials [4].
So the theoretical analysis is very important for the interfacial properties of carbon nanotube reinforced single crystal metal.
Molecular dynamics has been widely used to study the interfacial properties of carbon nanotube reinforced polymers [5].
Liu studied the interfacial properties of carbon nanotube and alumina matrix through molecular mechanics simulations[8].

In recent years, substantial studies and analysis have been carried out by targeting at the influential factors of contacts breaking characteristics.
For the spring system of the relay, the rigid part was built in UG software and then it was loaded into the ADAMS modeling environment while setting the material properties.
Then, it was loaded into the ADAMS to set modal properties.
In conclusion, thermal performance has not been adversely affected, as shown in Fig. 12 and Fig. 13.
The vibration characteristics meets the requirement of more than 2000Hz and thermal performance has not been adversely affected.

This paper aims to investigate the electrical properties differences between PEDOT:PSS doped SNP-based films and hydrogels.
Therefore, this work aimed to compare the electrical properties of the prepared PEDOT:PSS films and hydrogels doped with different silver nanoparticles (SNP) contents by drop-casting and freeze-thaw methods, respectively.
The morphological properties of PEDOT:PSS incorporated with SNP were observed by Scanning Electron Microscope (SEM), as shown in Figure 5.
This indicated the films mostly affect the electrical behaviour of PEDOT:PSS/SNP compared to hydrogels.
The findings are supported by the morphological properties of the films, which appears rough surface after adding SNP, thus believed to provide pathways for charges carrier in the material.

The rheological properties of chocolate were tested by Anton paar modular compact Eheometer: MCR 502 for analyzing flow behavior.
Mechanical platform.
Moreover, based on its pseudoplastic property, thermal change during machine processing also affected the size of the chocolate line.
Therefore, three fundamental variables and mechanical properties of the material were considered in this work to yield a constant width of the chocolate line.
Impact of rheological properties of mashed potatoes on 3D printing.

With ring-ball test sidewalls of samples are only little affected by the centrally applied bending force.
It should be mentioned that it was not our intention to determine the “best” grinding wheel but to find out how the differently ground silicon wafer surfaces behave in terms of their mechanical properties.
Here, we conclude that the thin silicon material exhibits its intrinsic material properties and the fracture strength is defined by bulk behavior of a non-distorted single-crystalline silicon lattice.
Additional stress-relief processes after grinding improve fracture strength significantly by a factor of 6 to 15.
Bagdahn; „Investigations of the influence of dicing techniques on the strength properties of thin silicon”; Microelectronics Reliability 47 (2007) p. 168-178