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For example, the organic polymer itself has a low dielectric constant, but the mechanical properties and thermal properties are poor, the adhesion force of which combined with the substrate is not strong, and to be unable to bear high temperature.
Through using different methods the low dielectric constants of PI film or particles are synthesized to have a variety of different structures and different properties, but the dielectric properties of prepared PI materials (including PI composites containing voids) still can’t reach the requirement of the development of electronics industry, and when the dielectric constant is reduced to 2.5 after the following the introduced void volume ratio of PI group is very high, resulting in the mechanical and thermal properties PI significantly reduced [9,10].
In addition, the mechanical properties and processing characteristics are the important parameters in determining the dielectric properties of materials.
A dielectric material for the large scale integrated circuit must meet the following basic requirements [18]: (1) a low dielectric constant with isotropic properties; (2) low moisture absorption; (3) excellent chemical resistance and heat resistance; (4) a good processing performance; (5) excellent electrical properties.
For example, add 0.5~2% of the ultrafine silica in PVC, it can obviously reduce the dielectric constant and dielectric loss factor. [19] The properties of low dielectric constant make the nanometer silica particles to be used for interlayer dielectric materials, which is widely used as a kind of dielectric materials with low loss.

The objective of this work is to develop a set of individual models which can be linked together to quantify how alloy chemistry and the thermal/deformation history combine to determine key processing parameters and the final properties of the product.
However, it is important to point out that these simple estimates do not consider kinetic factors, i.e. in some cases the microstructure is unrecrystallized after extrusion but will recrystallize if a post extrusion heat treatment is added (see reference [19] for more details).
Further, the complex strain path near the surface is expected to strongly affect the deformation texture in this region, thereby affecting the recrystallization texture.
The creation of the model allows for an analysis of interdependencies between different processes e.g. establishing how extrusion microstructure depends on homogenization practice and how variation in homogenization will translate to variations after extrusion, i.e. the linkage to final properties.
This allows one to look at the end product and determine which points in the process really dictate final properties.

With the help of the springback simulation, Moreover the factors, which are significantly affecting springback, were studied.
Wrinkles of parts is caused by large pressure of the blank during the drawing forming, and is mainly because of insufficient feeding resistance of the binder surface or the designed poor manufacturability of parts and other factors.
The springback is the redistribution of stress inside the forming sheet metal after unloading, and the accumulative effect of the entire forming process, seriously affecting the forming quality of the part [2].
And there are a lot of differences in the friction during the forming of auto-body panels and general mechanical friction.
Friction is one of the most important parameters affecting automobile panels.

The properties analysis of caprock For qualified UGS, injection gas could be stored in the reservoir, and gas could be kept for a long-time as required, which would not escape through the penetration channel.
Mechanical properties of rock decided the stability of caprock. if the stability of the caprock could not reach the minimum standard required, gas would break the caprock and flowed out from reservoir in the UGS, and loss was great.
Low initial permeability, compact structure, and stable mechanical property kept the sealing ability of caprock stable during injection-production cycle, while the Loose caprock was the opposite.
Influencing factors analysis of sealing ability Lithology and mechanical characteristics of rock were the main factors influencing the sealing ability of caprock.
At present, the research on influencing factors was focused on building relation equation between sealing ability and effective stress[16].

Microstructure and Mechanical Properties of fly ash/Al-25Mg Composites Processed by Powder Metallurgy Method Qingping Wang 1, 2, a, Yucheng Wu 1, b, Fanfei Min 2, c 1 School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China 2 School of Materials Science and Engineering, Anhui University of Science and Technology, Huainan 232001, China aqpwang@aust.edu.cn, bycwu@hfut.edu.cn, cffmin@aust.edu.cn Keywords：fly ash; aluminum matrix composite; friction and wear; wear mechanism.
They detected the property of this material, assessed its property and studied its probable prospect of application in components of machine.
When the fly ash is more than 10%, it will become glomerate severely and the consistency of the composite will decrease, and these factors affect the property of the composite.The hardness of the composite increases greatly with the increasing of fly ash in the composite.
Test load influences the property of friction and wear by the size of contact area and the degree of distortion.
So, the wearing property of fly ash particle/Al-25% composite will increase with the increasing of fly ash.

(2) Therefore, the cutting thickness e is an important factor affecting the cutting load.
The sample is able to come into the core institutions as much as possible on the condition that the sample to maintain the original form (to maintain the solid features) does not decompose under the influence of centrifugal force (fluid properties enhanced).
Ignoring friction of the support tube and soil cylinder, the mechanical model of the sampling process is as shown below:
The experimental results can provide the key parameters in the control process of coring drill. 5 Conclusion The large-depth lunar soil drilling & coring involves many aspects strongly coupled, including the driving parameters of coring drill, mechanical properties of lunar soil and their interaction.
This finding will benefit the coring drill control in the lunar soil with similar properties.

Investigated factors and their levels.
Box-Meyer method aims at discovering the active factors, that is those which significantly affect the response through their main effects and/or interactions.
It considers all the possible subsets of active factors, each subset stating a particular combination of factors as active.
Factors A, B and D (α1, α2 and H1) clearly stand out as active, while the remaining factors turn out to be unimportant.
Micari Influence of Mechanical Properties of the Sheet Material on Formability in Single Point Incremental Forming, Annals of the CIRP Vol. 53/1/2004 (2004), 207-210

Particle Flow Code (hereafter referred to as PFC) has been widely used in the study of the mechanical properties of rock and rock-like materials at the micro-scale [1-3].
PFC Model of Infilling Rock Joints The shear properties of infilling rock joints are affected by many factors, and infilling thickness and roughness are main factors.
In order to obtain the micro-properties of the established PFC model, an axial compression physical test is performed firstly, and the corresponding macro-properties, which are used to inverse the micro-properties of the PFC models based on the optimization inverison method, are listed in Table 1.
The inversion micro-properties are listed in Table 2.
Combined with fixed micro-properties, all micro-properties of the PFC model of rock discontinuities are consequently determined.

In the traditional mechanical polishing method, even though surface roughness is good after polishing, there still remains very slight polish mark and deformed layer.
It removes hydrogen which accelerates fatigue failures and bacterial growth, makes a shiny, lustrous surface, eliminates stress and decoration, improves adhesive properties, and brings about deburring effect.[2] Electropolishing principles The electropolishing based on an anodic dissolution process using an electrochemical reaction can produce both fine surface and stress-free surface.
Using electropolishing, the workpiece obtain excellent corrosion resistant by removing impurities, mechanical damaged layers, and material which form a nucleus of corrosion from the surface.
Electropolishing removes slag, burrs, scratches, heat affected zones, hydrogen of surface.
By combining these factors in further studies(machining parameter, electrode gap), better surface roughness and microburr removal effect would be achieved.To verify the microburr removal effect of electrolytic polishing, burrs were artificially created, and the sizes of the remaining burrs were measured after processing.

As a key part feature of the machine, machine tool spindle’s performance would directly affect the processing performance of the whole machine.
As the machine tool spindle had the feature of high complexity, many influence factors and small sample size, the phenomenon of less failure data or “zero failure” was often produced when life test was used in the machine tool spindle.
The reliability of production was connected with its physical properties by reliability analysis based on performance degradation data, degradation data was get through the change of product performance parameters, the degradation of products was analyzed with degradation data, then the reliability of product was evaluated before product failure.
Then, it was used in mechanical.
References [1] HE ZhengJia: Developments and Thoughts on Operational Reliability Assessment of Mechanical Equipment (Journal of Mechanical Engineering, China 2014)