Search results

Materials added to the matrix help improving operating properties of a composite.
Impingement angle, impact velocity, size and shape of the erodent particles, as well as the properties of target material are important variables that affect erosion wear [2].
The effect of nanotube content on the mechanical properties of polyamide-6 reinforced with basalt fibres was investigated by Meszaros et al. [10].
The experimental results showed that the combination of macroscopic and nano sized reinforcements improves the mechanical properties significantly.
Meszaros et al. [11] studied the mechanical properties of basalt fiber and montmorillonite reinforced polyamide 6 matrix hybrid nanocomposites.

Study on rock strength characteristic by point load test WANG Ruihong 1a，JIANG Yuzhou2b,GUO Jinlong3c,TANG Tiancai4d 1Key Laboratory of Geological Hazards on Three Gorges Reservoir Area，China Three Gorges University，Ministry of Education，Yichang，Hubei 443002，China; 2Key Laboratory of Geotechnical Mechanics and Engineering of the Ministry of Water Resources，Yangtze River Scientific Research Institute，Wuhan，Hubei 430010，China 3China Three Gorges University,Yichang，Hubei ，China 4China Three Gorges University,Yichang，Hubei ，China a43604258@qq.com , bjiangyuzhou5586@163.com, c125317331@qq.com, d444136942@qq.com Key words: Rock specimen; Mechanical test; Point load; Uniaxial compressive strength Abstract：Test point load test requires relatively small load, its instrument is portable, it can be easily applied to on-site testing,which may pave the way for the development of the fieldstrength of rock mechanics test, widely promoted in engineering construction, has a large space for development
Introduction The mechanical strength of rock is an important parameter for rock engineering designing, constructing, its accuracy directly affects the security and stability of the construction and operation, as well as the economic rationality of construction[1-5].
Fig.1 SD-1 Point load instrument author emprical formula Broch & Frankln Rc=29.07 Is（50） International Society for Rock Mechanics Rc=（20~25）Is（50） Chengdu College of Geology Rc=（18~19）Is（50）(minor axis) Rc=23.7Is（50）(macroaxis) Northeast Institute of Technology Rc=65+17.4 Is（50） Second survey and Design Institute of Railways Rc=22.819Is（50）0.745 2003,Quane and Russel sterosome Rc =24.4Is50 weak rock Rc =3.86（Is50）2+5.65Is50 In 2004Tsiambaos and Sabatakakis Rc =7.3（Is50）1.71 Rc =23Is50 In 2005 Fener Rc =9.08Is50+39.32 In 2009 Sabatakakis Point load <2Mpa Rc =13Is50 Point load 2~5Mpa Rc =24Is50 Point load >5Mpa Rc =28Is50 S.Kahraman ·O.Gunaydin weak rock ：Rc =8.20Is+36.43 metamorphic rock：Rc =18.45Is-13.63 sedimentary rock ：Rc =29.77Is-51.49 《Test procedures of physical and mechanical properties of rocks》 Rc=22.77 Is（50） 《Standard for engineering classification of rock mass》GB50218-94 Rc=22.82Is（50）0.75 Rock test specification for Railway Engineering(TB 10115-98) Rc=24.3382Is
The shape and dimensions of the sample, lithology and structure factors directly affect the Rc and Is(50) the relationship.

The reasonable agreement between the two data sets indicated the validity and provided a theoretical basis for using computational methods for determining the natural characteristics and influencing factors of HSK tool system.
One can see that the dynamic performances of the tool system are among the important factors to ensure the machining process stable and reliable.
The Experimental Verification of HSK Standard Shaft Free Mode We have got the structural modal parameters of HSK63A tool system with the finite element method, but there are some factors which affect the calculation accuracy such as minutiae feature and size of mesh.
At present, EMA has become the most important method of vibration analysis in the mechanical engineering.
The results further indicated potential use of this method for studying the dynamic properties of HSM (high-speed machining) spindle-tool systems.

Introduction Since the discovery of carbon nanotubes in 1991 by Iijima [2], numerous experimental, theoretical, and computational investigations have been performed to investigate their superior and unique chemical, electronic and mechanical properties.
Owing to these extreme properties, carbon nanotubes are ideal candidates for NEMS, which open up a vast area of potential applications such as pressure and mass sensors, nanotweezers, RAMs, and actuators [3, 4].
The applied gate voltage bends the nanotube and affects both the nanotube’s electrical and mechanical properties (See Fig. 1 for a schematic).
The applied gate voltage pushes electrons inside the nanotube downwards by the electrostatic force which alters the nanotube’s mechanical properties.
Hierold, From micro to nano systems: Mechanical sensors go nano. 14 (2004) 1-11

Effect of Aging pH Value on the Properties of Porous SiC Ceramics Produced through Coat-mix Process Hui Yang a, Hongsheng Zhao b, Zhongguo Liu, Ziqiang Li and Kaihong Zhang Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China ayanghui-502@163.com, bhshzhao@tsinghua.edu.cn Keywords: Porous silicon carbide ceramic; Coat-mix process; Aging pH value; Crosslink degree.
Introduction Porous ceramic materials have many excellent properties, and are widely used in many disciplines.
It is found in application that porous ceramic materials need further research and improve in the following aspects: thermo- mechanical properties, porosity and strength, materials aperture control, and production costs.
The aging environmental pH value is found to be a variable quantity for curing rate and crosslink degree, and an adjective factor to achieve improved performance of porous SiC ceramics.
It indicates that some other factors can affect the strength of porous ceramics besides the porosity.

However, tendon damage and defect remain an important factor for causing disability.
(2) whether it is possible to generate tendon tissue in vitro and how mechanical training affects the structure of engineered tendon. (3) whether it is possible to use other cell source to replace tenocytes for tendon engineering.
More importantly, the in vivo engineered tendon exhibited enhanced mechanical property with times.
Among the tendon engineered with various time periods, it seemed that tendons with 8-10 weeks of in vitro culture had the best tissue structure and mechanical property.
In the in vivo study, we also demonstrated that dermal fibroblasts could replace tenocytes to generate tendon graft that had tissue structure and mechanical property similar to that of tenocyte engineered tendon.

The Effect of Aluminum Clad on the Electrochemical Properties of the Similar Weld of Friction -Stir Welding of 2524 Changbin Shen, Jiayan Zhang, Jiping Ge, Feng Yan Liaoning Key Materials Laboratory for Railway and School of Materials Science and Engineering, Dalian Jiaotong University, 794# Huanghe Road ,116028,Dalian,China email:shencb@djtu.edu.cn Keywords: aluminum alloy; alclad; friction stir welding; microstructures; electrochemical corrosion Abstract.
Friction stir welding (FSW) was invented at The Welding Institute (TWI) of UK in 1991 as a solid-state joining technique that unites thermal and mechanical aspects to produce a high quality joint, and it was initially applied to aluminum alloys [1].
Then, in the ambient temperature solution of 0.2M NaHSO3 and 0.6M NaCl, by static weight loss experiment (gravimetric test) and potentiodynamic polarization curve, the effect of aluminum clad on the electrochemical properties of the similar weld obtained by FSW of 2524 was investigated.
The welded alloy showed the expected zones associated with friction stir welding, namely heat affected zone (Fig.1 (b)), thermomechanically affected zone (Fig.1 (c)) and nugget (Fig.1 (d)).
After intense plastic deformation, the pronounced physical irregularities were reduced and nearly chemically homogenous [3,4], the beneficial factors will overcome the increase of residual stress and make less prone to emerge localized attack microcells in the weld surface, then make FSW welding weld get more resistant to the aggression of HSO3- and Cl- ion.

And the terrain environment interact with each other is the properties concrete manifestation of a complex terrain mobile robot.
,considerring terrain factors influence are essential.
To deal with the influence of complex terrain conditions on the mobile robot,in the paper, a novel motion modeling idea used in the duct cleaning robot is proposed, which real-timely measures the robot chassis attitude angle changes caused by the topographic changes, and the attitude angle is input into the robot kinematic modeling process, then the end of the position and attitude affected by both of the terrain and robot is got , so as to establish the overall kinematic model of the robot.
Based on this model, robot can achieve effective control in complex environments. 1.Influence analysis of duct cleaning robot model on the complex terrain Duct cleaning robot is a kind of crawler mobile robot used for cleaning the ventilation pipe of central air conditioning,which works long time in complex, varied terrain ventilation pipes.There are slopes, obstacles and other unforeseen factors in the pipes(Fig. 1).Influenced by terrain and obstructions and other factors ,the robot posture changed during the moment,which increased many uncertainty factors for the robot kinematics.
Mechanical Engineering.2008, 44(6),148-154

Introduction For the injection molding is one of critical process in the field of industry, it possesses high product rate, shorter formation cycle, low waste rate, smooth surface and easy in complicated shape formation; the precise of LED lampshade is very small, factors of insufficient filling during the process, warp and residue stress, all these defects are the cause affecting the formation of LED lampshade.
For the plastic, relation of the variables of physical property and temperature shear rate are dependent.
Fig. 5 shows response diagrams for all control factors of the injection process.
The confirmation test is a repetition of the experiment, optimal control factors is used to obtain the predicted quality characteristics
Factors A, D and F have less influence and is pooled as error. 3.

Under actual operating conditions, the reinforced-concrete structures are subjected to a comprehensive effect of aggressive factors, which are greatly enhanced in the conditions of high temperatures and fire.
The main factor that affects the reinforced-concrete structures under the influence of the above factors is the loss of strength characteristics that results in the destruction.
Under conditions of high temperatures during fire, the fire resistance of the protected reinforced-concrete structures is affected by the phase composition of the coating due to a significant difference in thermomechanical properties.
Such properties of coatings as durability and protective ability under operating conditions greatly depend on the degree and stability of adhesion strength.
The presence of the latter contributes to the synthesis of new phases, which positively influences on their properties.