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Effects of nanostructures on physical and mechanical properties and radiation performance with neutron and light ions such as 3MeV He4+ and 1keV H3+ are presented.
Thermal properties Thermal properties such as the coefficients of thermal expansion (CTEs) and thermal conductivity are very important.
Mechanical properties Mo and W exhibit ductile-to-brittle transition behavior which is typical of group VI transition metals.
The microstructural and processing factors that are influential to the Mo alloys will be addressed.
The high temperature mechanical properties (elongation, flow stress, m-value) that are essential to plastic working can be optimized by TiC addition and MA atmosphere. 3.

The structural and morphological properties were investigated using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM).
Introduction Zinc oxide (ZnO) is an interesting material due to their excellent physical and chemical properties.
ZnO nanostructures have a good mechanical strength, thermal and chemical stability.
Nanostructural ZnO formation is influenced by many factors in the hydrothermal process, which suggests the morphologic varieties of the nanostructures.
The SEM images revealed that the amount of ammonium in the hydrothermal process affects the morphology of ZnO nanostructures.

Introduction Boring axle is one of the important components of NC boring and milling machine, its working conditions directly affect the machining performances and processing quality of parts.
In addition to the above machining requirements of each surface, quality control and selection, heat treatment of material are also researched in order to improve integrated mechanical properties of parts.
Technical Design of Boring Axle Processing Because the boring axle often works in high-speed, high-torque condition, and the boring axle suffers alternating stress, the boring axle must have properties of good wear resistance and higher fatigue.
Therefore, a simplified axle structure and mechanical model is shown in Fig. 2.
Fig. 2 Simplified structure and mechanical model of boring axle Process and Results of Finite Element Analysis.

Li et al. [8] examined the effects of the number of extrusion passes and the processing routes on the mechanical properties of PC.
Xia et al. [10] found that the crystallinity and the molecular orientation are the major factors affecting the dynamic mechanical properties of semicrystalline polyethylene terephthalate (PET) extruded by ECAE.
Its thermal properties were obtained by differential scanning calorimetry (DSC) analysis.
The mechanical measurements were achieved at room temperature on an electromechanical Instron© testing machine.
It is also of interest to complete this study by mechanical and morphological characterization of the material after ECAE deformation.

Although domestic scholars have done some researches on factors contributing to the impact on mechanical behavior of joints and have collected the calculating ways of the thickness of the beam overhanging terminal plates [4~6], their researches are still in the starting stage.
The factors that influence the seismic behavior are also mentioned in the article.
Selection of the Nodes Changing Parameters Because the complex stress of the semi-rigid joints, it is affected by many parameters.
Many series of specimen are designed and derived from BS specimen to study the each parameter’s influence on its mechanical performances.
The Property of Semirigid Beam-to-column Connection of Multistory and Highrise Steel Frame Structure.

Design and magnetic field simulation of Giant Magnetostrictive bone conduction pronunciation vibrator ZHAO Zheng-long*, HE Zhong-bo, LI Dong-wei, XUE Guang-ming, YANG Zhao-shu Department of Vehicles and Electrical Engineering ShiJiazhuang Mechanical Engineering College ShiJiazhuang, China 498836250@qq.com Keywords:Giant magnetostrictive; bow type structure; vibrator; simulation Abstract.
Giant magnetostrictive material (GMM) has the characteristics of big magneto-mechanical coupling coefficient, enormous strain and broad frequency response, which is widely used in audio and ultrasonic technology, ultra precision machining, testing technology, fluid control, vibration control and all kinds of sensors in recent years.
With the traditional magnetostrictive material and piezoelectric ceramics (PZT) compared to the GMM has the following advantages [5.6]: (1) The dependent variable is very big, in terms of the value of the magnetostrictive strain, it is better than pure Ni and piezoelectric materials 30 and 3 ~ 5 times greater respectively; (2) The output force that strain produces is very big, and the load capacity is strong which can reach 220 ~ 800N; (3) Electromechanical coupling factor K33=0.7 ~ 0.8, significantly higher than that of the piezoelectric ceramics and other materials; (4)The Change of the elastic modulus can be controlled due to the change of the magnetic field; (5) Response time is very short, only 10 ~ 6S; (6)The frequency characteristic is good, frequency band is wide, the ability converted into mechanical energy is better than any other material in the range of 0 ~ 5 KHz; (7) The stability characteristics are good with very high reliability, the magnetostrictive properties
Because of the stationary fixed surface, bending deformation of tapered bow structure on both sides is finally converted into the mechanical vibration of the output surface to the right along the graphic direction of the vibrator, realizing the audio signal transmission of bone conduction device.
The output surface, fixed surface and the bow structure are of the same material which is set to be the low magnetic or high magnetic materials respectively, but the output end and the fixed end does not belong to the vibrator magnet circuit so that the internal magnetic field of GMM rod will not be affected, therefore both of them will not be considered in the analysis.

While improving the machining rates will go a long way towards increasing the usage of the material, it must be noted that this is only one of the number of factors affecting the use of the material.
Zoya and Krishnamurthy [24] have discussed the factors that affect the machining of titanium and its alloys.
Shane et al [26] have reported how the temperature affects Ti-64 alloy properties and they have proposed a new economical cryogenic cooling approach.
It is interesting to note the good mechanical properties of the titanium alloys with respect to steel but relatively poor thermal properties (Machining Hand Book [56] and Materials Properties Hand Book [57]).
Cutting temperature has been recognized as an important factor affecting the tool wear rate and tool life.

The influence of the addition of spongilites on the physico-mechanical properties, frost-resistance, and microstructure of cement mortars as a function of time was studied.
Fresh state properties of cement-spongilite mortars.
Summary This paper has focused on the effect of two types of spongilites on the fresh state properties, mechanical properties, microstructure, and frost resistance of cement mortars.
Šrámek, Relationships between mineralogy, physical-mechanical properties, and durability of cretaceous calcitic spongilites, in: J.
Rovnaníková, Pozzolanic properties of brick powders and their effect on the properties of modified lime mortars, Constr.

The part structure of concrete slab likely is crazed by the effect of tension and compression,and concrect ecclasis occurred.： 脱落，破碎；脱落, 破碎.According to the traffic situation at present in da-qin railway, part of its existing slab culvers can not meet the total needs of overloading,long-term operation will make the slabs of the culvert structure damage aggravate even fatigue damage, it will affect safety of train operation.
At present, the domestic and foreign research mainly aims at reinforced concrete beam component about reinforced concrete structure of the fatigue performance and prediction of fatigue service life, and it obtaines some achievements. [1]draws a reinforced concrete beam bridge will not aggravate fatigue damage with axle load 25 tons; [2]~[4]puts forward residual life prediction method based on the system reliability for existing reinforced concrete beam, and establishes corresponding mathematical model; [5]shows that the effect of heavy haul train is little to small span bridges ; [6] analyses the reinforced concrete beam fatigue damage for 8 meters span and evaluates the service life,it show that existing bridge cannot achieve fatigue damage in da-qin railway currently. the domestic and foreign little research aims at fatigue performance of reinforced concrete slab structure and the prediction of fatigue service life, but for recearch on roof and bridge panel, and the lesser fatigue properties
Then uninstall to zero,next for second crack test(second static load), it is used to determine crack well.numerical examples deformation property and stress conditions, stop loading until achieving unprotected ground reinforced concrete structure crack width allow value at general atmospheric conditions when loading until producing 0.2 millimetre crack in beam[6].
The fatigue strength analysis of tensile steel :The steel fatigue is the result of crack initiation and expansion for fatigue loads, the stress balance of crack tip is broken when the stress intensity factor reached critical value,and the crack expands until the new balance is reformed as the equilibrium process of continuous cycle until steel cannot make crack tip stress strength balanced then ruptured.There are many factors for fatigue strength, such as stress amplitude, the smallest stress level, reinforced appearance, diameter and strength, but stress amplitude impacted is the most important.
The calculated value of tensile steel fatigue life Strain amplitude of the tensile steel （με） Stress amplitude of the tensile steel （MPa） Calculating fatigue life times（million times） 344.24 68.85 183.10 345.34 69.07 180.28 297 59.40 374.71 The steel stress variation is very complex with fatigue loads,and it’s influencing factors is various.We carried fatigue test of reinforced concrete cover in order to study stress law of development of steel and reinforced concrete(the fatiguelife is more than 2 million times ) of reinforced concrete cover plate on fatigue- normal using state.

Meanwhile, a numerical simulation based on the Pro/ENGINEER software was conducted in order to study the relationship between stick slip behavior and its impact factors, such as the mass, stiffness, friction coefficient and damping coefficient.
Also, computer simulation is carried out to prove the relationship between the different factors according to the equations derived.
Above-mentioned analysis demonstrates the existence of the relationship between the stick slip behavior and its factors in theory.
Fig. 2 The virtual prototype of positioning stage In the module named “Mechanism”, objects on the guide, spring and damper between them are contained given separate properties.
Afterwards, numerical simulations of the mechanical system based on the CAE technology are taken which have proved the correction of the theoretical analysis.