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Flatness is one of the key indicators to measure the quality of rail, rail flatness directly affects speed, safety and comfort of trains[1].
The rail curvature before straightening directly affects the flatness after straightening from the theory and actual production, and the rail flatness which has greater curvature would be worse after straightening at the same deformation conditions.
In this paper, based on the simulation results of the rail whole rolling process, thermo-mechanical coupled simulation of 60kg/m rail during cooling process has been simulated and bending deformation, temperature filed distribution have been studied.
Considering the influence of temperature on the mechanical properties, basic material parameters relating to temperature are needed to define in the thermal mechanically coupled calculation for rolling process, such as density, density, elastic modulus, poisson ratio, yield strength, at the same time the basic thermodynamic parameters are also needed to define, such as the specific heat and thermal conductivity.
With the growth of the cooling time, the effect of radiation and convection on the rail cooling was reduce, and the influence of thermal conductivity increased, the rail internal heat transfer become an important factor affecting the temperature of the rail key points, the rail cooling rate slowed down, and the temperature difference of the rail key points decreases gradually, and finally become the same.

Ceramics are widely used in every field of contemporary industrial because of its many excellent properties.
Therefore, how to improve mechanical properties of ceramic materials has been attracted a great attention in the relevant area.
Domestic and international research has shown that, boundary constraint is an effective way to improve mechanical properties of materials.
The value of constraint force also affects load capacity.
It jumps out of the traditional design framework of materials structure and has many excellent properties.

For CMP process, all sorts of factors, including particles or contaminations, macro aggregate abrasive particles, polishing by-product filling polishing pad, and other factors (for example the dissolved gas and light effect), may influence the uniformity of the wafer surface[4-5].
It is very important to strengthen the mechanical effect in order to improve the material removal speed and restrain chemical effect.
Friction capability affected by the size, shape, the structure of abrasive particles and surface charge distribution is an important parameter of mechanical effect, especially to remove material speed of CMP process.
Optical end point detection can be set arbitrary thickness according to the infrared interference detection; the motor current detection depends on different drive current caused by different materials friction properties; polishing pad temperature test belongs to indirect testing technology as the former two detection added usually. 3.
Investigation of optical properties of benzocyclobutene wafer bonding layer used for 3D interconnects via infrared spectroscopic ellipsometry.

These were found on fracture surfaces which served as an origin of creeping failure mechanism and are the most important factor for failure of this blade.
Three probable damage mechanisms affect turbine blades, these being mechanical damage through either creep or fatigue and high temperature corrosion .However, materials used for turbine blades must be suitable in these conditions.
The γ' phase shows an unusual property in that it tends to increase in strength with increasing temperature, at least at lower temperatures below about 973ºK.
Finally the presence of rafted γ' phase on the grain boundary under aging phenomena and diffuse elements such as S via surface crake are most important factor to failure of blade.
Ye, Microstructure and mechanical properties of cast Ni-base superalloy K44, Materials Science and Engineering A 374 (2004) 327-334 [5] M.

Introduction The particle-reinforced aluminum matrix composites have an excellent physical mechanical properties but it was also a typical difficult to cut material.
Because electroplated diamond wheel had the properties of easy production and low cost, it could substantially reduce manufacturing cost of processing particle reinforced aluminum matrix composites.
It was affected by multiple factors.
Generally, factors which made surface temperature higher could increase tension stress of the processed surface; however factors which enhanced plastic deformation of the surface could increase compressive stress of the surface.
Tangential force and normal force were relatively lower and not obviously affected by grinding parameters.

Modeling and Simulation of Chilled Water System for Central Air Conditioning Jianmin Sun 1, a, Chundong Zhang 1, b and Zeyang Zhou 1, c 1School of Mechanical-electronic and Automobile Engineering, Beijing University of Civil Engineering and Architecture, Beijing, China asunjianmin@bucea.edu.cn, b winter5515@163.com,c zhouzeyang123@163.com Keywords: Central air conditioning; Chilled water system; Mathematical modeling; PID control Abstract: Considering the central air conditioning system is highly susceptible to interferences from external environment, this paper established a dynamic mathematical model for chilled water system with the air conditioning area, fan coil unit and air conditioning area interference factors.
Introduction Central air-conditioning systems as a big energy consumer in commercial buildings, the energy saving effect is directly affect the integrated building energy efficiency.
Establish the air conditioning area mathematical transfer function model In terms of central air conditioning system, air conditioning area is influenced by many factors; its thermal equilibrium is a complicated process.
Establish the interference factors of air region mathematical transfer function model Room temperature interference factors: internal disturbance (indoor lighting, personnel) and disturbance (outdoor air through the structure enters into the interior).
In order to not affect the simulation results while ensuring the precision of control system, this paper adopts approximation of two order mathematical model.

Introduction The vibration of NC machine in the process will make relative position between workpiece and tool changed, affecting machining precision and efficiency of the workpiece.
The natural frequency and principal mode of vibration system is the natural property, which could be got through no damping free vibrations.
(1) From the modal cross dynamic flexibility of r order, the primary influence factors on dynamic response of machine system are natural frequencies and principal modes.
The main work includes: (1) Analyze and summarize the ant-vibration performance factors of NC machine, clear the inherent characteristics to be the key factor of forced vibration and improve the ability to resist the self-excited vibration under the situation of balancing the distribution of energy and damping distribution through reducing every order Modal flexibility and increasing every order damping ratio
[6] Tang Guoxing, Yin Feihong: Mechanical design and manufacturing, Vol. 12(2007), p.21.

Factors for influencing the stability of steel slag The volume stability is one of the important characteristics to measure whether it is qualified or not while steel slag was used in building materials field as a kind of cementitious materials.
Mechanical modification Mechanical modification of steel slag is to make ultrafine steel slag under the strong mechanical force, increase the specific surface area of steel slag, making large amounts of free CaO and MgO exposed and hydrated fast.
Sun, The effect of grinding fine steel slag on the mechanical properties and stability of the admixture of cement and concrete, J.
Xu, The research of hydration properties of steel slag powder as auxiliary cementitious materials under the different water heat conditions, D.
Lian, et al, The property of iron tailings of high temperature used as modified steel slag, J.

Aftershocks and heavy rain conditions will induce secondary geological disasters, a direct threat to human life and property security and reconstruction results.
After this, the method of strength reduction is used to analyze slope safety factor in different rainfall conditions.
Introduction Slope landslide is because of all sorts of factors coupling deformation, was eventually some inducing factors stimulate happen instability, produce sliding a disaster geological phenomenon.
As the two major natural landslides induced factors: earthquake and rain, both the cause of the mechanism completely different.
Using strength reduction method analysis of the different rainfall conditions of slope safety factor change trend, with the increase of rainfall, the softening parameters, the slope safety factor of slope sliding, decreasing gradually.

To achieve the best functionality of the coatings one needs to know the relationships between the mechanisms of coating formation and its mechanical properties.
While the mechanisms of formation of such coatings have been rather well investigated, detailed information on mechanical properties still remains difficult to obtain because of the heterogeneity of the coating [1].
Fig. 1 SEM micrographs of the WC Co coating 2.2 Scratch test measurements The mechanical properties and especially adhesion of the coating to the substrate were evaluated by the scratch test using the tester Millenium 200.
The differences were explained by the volume of the material affected by the process of indentation.
Petit, Characterization of mechanical properties of suspension plasma sprayed TiO2 coatings using scratch test, Surface & Coatings Technology 202 (2008) 2644-2653