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Introduction The properties of advanced polycrystalline materials depend critically on the properties of interfaces such as grain boundaries (GBs).
In particular, interaction between GBs and melts in structural materials may be the reason of deterioration of mechanical properties and failure.
In order to determine the factors affecting growing kinetics, the experimental penetration rate was compared with one predicted by Mullins for volume diffusion controlled GB grooving [3]. 10 100 10 15 20 25 30 35 40 ϕϕϕϕ,° t, hours 1 10 100 10 100 tgαααα=0.49±0.05 αααα Mullins (d~t 1/3 ) d, µµµµm t, hours a b Fig.3 Dependence of contact angle (a) and penetration depth (b) on annealing time. 3 1 2 0 2 01.1       = t RT DVC tg d mslσ ϕ (1) Following values were used for quantitative calculations: equilibrium concentration of Zn in Sn melt at 325°C C0 = 5.13·104 mol/m 3 [4], σsl = 150 J/m 2 at 200°C and dσsl/dT = −0.29 J/m2 [5], Vm = 9.2·10−6 m 3/mol, DZn(Sn) = 1·10−8 m 2/sec [6].
The change of grooves morphology of with time of annealing more 78 hours that denotes that for the very long annealing time the diffusion will probably become the limiting kinetic factor.

The conductivity γ represents the conductive properties of the material.
Conductivity will be affected by temperature and humidity, the conductivity of the silicone rubber is proportional to temperature and humidity.
The arc will increase the silicone rubber tube’s dielectric constant ε and dielectric loss factor tgδ, and then decline the electrical insulation property of the tube.
Conclusion The relative dielectric constant ε, the conductivity γ, and the dielectric loss factor tgδ of the silicone rubber tube is low when the tube works under frequency voltage.
[2] Yao-nan Liu and Changrang Qiu:Electrical insulation testing technology(Mechanical Industry Press, Beijing 1981) ,in Chinese

The Inverse Prediction for Profile Extrusion Die Based on the Finite Element Method Min Zhang1, 2,a, Chuanzhen Huang 1, 2, b, Yuxi Jia 3, c ,Jinlong Liu 1, d, 1School of Mechanical Engineering, Shandong University, Jinan 250061, China 2Ministry of Education Key Laboratory of High Efficiency and Clean Mechanical Manufacture, Shandong University, Jinan 250061, China 3School of Material Science and Engineering, Shandong University, Jinan 250061, China a zhangmin2616@sdu.edu.cn, bsdu_huang2013@163.com, cjia_yuxi@sdu.edu.cn, dliujinlongfirst@163.com Keywords: Viscoelastic Fluid; Extrudate swell; Inversed simulation; Finite Element Method; Die design Abstract: Considering the extrudate swell, the polymer extrusion process was calculated by the inversed simulation based on the visco-elastic ecology theory.
There are so many factors, such as the material properties, molding temperature, and extrusion speed, which affect the results.
The area of the die lip is 21085.4 mm2.Compared to the product section area, 225600 mm2, the extruded swell ratio is 21.411%.Because of the extrudate swell affect, there are quite difference between the shape of the die lips and product section.

The performed theoretical studies and numerical calculations made it possible to carry out practical tests and develop conditions under which the physical effect of laser energy causes minimal damage to the alloys and composites of the sample, as well as to assess the effect of the laser on the properties of materials used in the aerospace industry.
In this paper, in order to take into account many different factors affecting the course of the technological process of laser cleaning of paint coatings from the surface of a sample made from a wing element of an aircraft of the Sukhoi Design Bureau, the temperature fields in the laser radiation zone are researched during the selective removal of a thin layer of AK-5178M paint with an ytterbium fiber laser YLR-150/1500-QCW-MM-AC [13-15].
M.: Mechanical engineering, 1951
M.: Mechanical engineering, 1984
M.: Mechanical engineering, 1985

Influence factors in the durability of concrete, in addition to chlorine salt corrosion, frost damage is an important factor of affecting the durability of concrete construction.
The study about mechanical properties of concrete frost resistance Dalian University of Technology has been some progress, a large number of test studies made by using triaxial test machine developed by Dalian University of Technology, on the basis of biaxial test of ordinary concrete ,they create a simple easy to use concrete failure criteria by studying characteristics of biaxial failure envelope and the trend of stress-strain curved, which make calculation model similar to actual engineering stress state, and thus be able to provide the test basis and more analysis methods for the design and durability analysis of this kind of structure.
For the current research about mechanical properties of concrete after freeze-thaw cycles, are all on the premise of a large number of test specimen as the specimen were damaged, on the study about mechanical properties of concrete after freeze-thaw cycles, many scholars regard freeze-thaw cycles of concrete as the process of fatigue damage, and lead damage variable point of view in the damage mechanics to analyze the failure criterion of concrete.
Because of material properties of concrete are complicated variable, and the multiaxial strength and deformation have great differences with the difference of multiaxial stress state.
(In Chinese) [10] Yu Maohong: submitted to Int J of Mechanical Seienee, Vol, (25)(1983), p.71

MEMS based resonators with tens of square microns in size have been showing great quality factors (Q) of more than 10,000 in research lab for more than a decade.
This problem mainly caused by the changeable physical properties of the materials according to the around environment, such as the temperature, and the complicated manufacturing process.
The thin film SiO2 is used as the first layer of the resonating element because of its high inherent mechanical quality factor and stress free properties.
So the change of will not affect the resonance frequency of the resonator.
White, MEMS Mechanical Sensors, Artech House, Boston, 2004

In system operation process, there will be a strong shock on the entrance section when revolving speed comes to 700 r/min; and the coupling will vibrate acutely at the speed of 1100r/min; at the speed of 1770 r/min and 2080 r/min, the mechanical seal makes strange sound; 2700 r/min or so mechanical seal can obviously improve the temperature and mechanical seal oil liquefied and local carbonization phenomenon.
Analyze the causes, the possible factors are the oil heating effect and the oil type that cause the single screw expander cannot fully apply work in low temperature or give full play to its cooling capacity.
In addition, thermocouple's low measuring accuracy and mechanical seal leakage factors may also influence the export's temperature measurement, thus affecting the judgment.
Table 1 Partial parameters of the state of the best value appeared Category Torque Speed Power Inlet flow rate Temperature difference pressure ratio Air rate Overall efficiency N·m r/min kW m3/h ℃ kg/kW·h % Power 15.4 2703 4.4 32.6 43.8 5.4 60.8 51.5 Air rate 17.2 2319 4.2 27 44.9 5.7 55.2 55.3 Overall efficiency 12.9 3022 4.1 29.1 40.9 4.9 55.4 58.8 Temperature difference 17.6 2275 4.2 28 45.0 5.9 57.7 52.3 Conclusions With compressed air as working medium, the properties of the new developed single screw expander was experimentally investigated with the pressure range from 0.75 MPa to 0.85 MPa.
Mechanical Industry Publishing House, in Chinese, 2000: 154-155

Some suggestions on the cladding material properties are done.
Dvi0 and Dbi0 are the pre-exponential factors that are related to the volume (0.01cm2/s) and boundary (0.001 cm2/s) diffusion of fission fragment, respectively.
Singh, Elastic, diffusional, and mechanical properties of carbide and nitride nuclear fuels – a review, J.
Clough, Creep properties of oxide and carbide fuels under irradiation, J.
Mechanical properties and microstructure of three Russian ferritic/martensitic steels irradiated in BN-350 reactor to 50 dpa at 490 °C, J.

The moving characteristic of materials is the basis of calculation of the load resistance during this process, and it is often based on materials deformation proposed analysis calculated mechanical model, and judged the magnitude and direction which generated by a variety of resistance, thereby determined the loads, it is as the basis of design and use of the machine.
It can achieve three-dimensional modeling and simulation, intuitive and accurately obtain the deformation characteristics and load spectrum of material - mechanical system.
Moreover, a larger friction factor is adopted to compensate for the error caused by the difference of spherical and irregular lumps. 2) Particles is assumed an inviscid unit body and squeeze destruction and bond are not occurred during loading. 3) Bucket inserts the materials at a constant speed
The angle between bucket bottom plate and the horizontal plane is about 3degrees, bucket bottom length 300mm and bucket width 300mm. 2) Material model: Rock materials, its material properties and contact properties are shown in Table 1 and Table 2.
The formation of dense core is the main factor for affecting the inserting resistance and this model can further study the factors that affect the existence of dense core

Reinforcement is subject to corrosive processes, which are affected by several factors.
The most important factors include content of certain pollutants in the concrete (chloride ions, presence of acids and other aggressive media), humidity of the environment, filling the pore system of the concrete with water, cover of reinforcement and concrete carbonation depth.
The corrosion does not affect the change in cross-section.
This type of corrosion is the borderline in terms of negative impact on mechanical properties.
[5] Effect of corrosion on the properties of steel prestressing reinforcement, team of authors, Klokner Institute, CTU.