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Alumina-carbon refractories are the prevalent family for slide gate application due to their superior thermo-mechanical properties.
This approach resulted in a material composite that jointly exhibits the thermo-mechanical properties and abrasion resistance of alumina based refractory and the corrosion resistance of magnesia based refractory.
This paper will present the properties, key limiting factors, and results of usage at three steel plants.
This advancement of carbon bonding has led to improvements in strength and thermo-mechanical properties, and as a result of this complex technology and further refinement, plate life has increased multi-fold.[] M.
The key thermo-mechanical properties were found similar to to the 1st generation material but a significant improvement in abrasion index was observed.

However, since the influence factors of shrinkage and creep characteristics are really extensive and complex, so far no theory can fully explain and accurately predict the shrinkage and creep properties of concrete.
Based on comprehensive and thorough study of development mechanism and influencing factors of shrinkage and creep, the author found that the following three factors in ACI 92 model should be corrected.
Correction of influencing factors Slump factor correction.
For the pumping high performance concrete, the water-reducing agent can greatly improve the slump and liquidity of concrete, without affecting water-cement ratio or water content of concrete, and also no significantly impact on other mechanical properties of concrete.
However, factors-such as the amount of cement, water cement ratio, aggregate condition and curing condition-that affect the shrinkage and creep can not be predetermined, while these factors are all associated with concrete strength in different degree.

Introduction The properties of carbon nanotubes are very excellent.
Currently, researches in the domestic and foreign are mainly focused on cement paste or mortar, but seldom on the properties of concrete composite with few carbon nanotubes.
As modern engineering structure is mainly based on the concrete structure, whether concrete composites with CNTs can have good mechanical-sensitive properties should be further researched.
So taking other affecting factors and mechanical enhancements into consideration comprehensively the optimal content of CNTs is 0.2% and 0.3%.
Cement based composites containing a small amount of carbon nanotubes perform well in mechanical-sensitive property, and the experimental results demonstrate that mechanical-sensitive property is influenced by two factors mutually.

The structural physical properties are often uncertain due to manufacture errors, measurement errors and other factors.
However, due to the manufacturing errors, measurement errors and other factors, structural geometric properties and mechanical properties are usually uncertain.
However, due to the presence of uncertain factors, classical optimization method cannot solve structural design problems effectively.
Rao [5] discussed probabilistic optimization of design parameters for a mechanical system under random vibration circumstances.
The result means the fundamental frequency of non-probabilistic method is the least affected by uncertain parameters.

During hot forming the mechanical properties of blank and tools change with temperature.
The coupling effect of the properties of blank, properties of the oxide film covering blank surface and viscosity of lubrication oil on friction coefficient have been discussed in detail.
Material mechanical properties The mechanical properties of 22MnB5 steel sheet are extracted from Shapiro [12].
Table 1 The material mechanical properties of 22MnB5 steel sheet T[] 20 100 200 300 400 500 600 700 800 900 1000 E[GPa] 212 207 199 193 166 158 150 142 134 126 118 0.284 0.286 0.289 0.293 0.298 0.303 0.310 0.317 0.325 0.331 0.343 p 4.28 4.21 4.10 3.97 3.83 3.69 3.53 3.37 3.21 3.04 2.87 c 6.2e9 8.4e5 1.5e4 1.4e3 258 78.4 35.4 23.3 22.2 30.3 55.2 k[W/mC] 30.7 31.1 30.0 27.5 21.7 23.6 25.6 27.6 Cp[J/kg] 444 487 520 544 561 573 581 586 590 596 603 True stress (MPa) Friction coefficient C A B True strain Temperature () Fig.3 The stress-strain curves under different Fig.4 Curves of friction coefficient vs. temperature temperature for 22MnB5 sheet steel Process parameters The strength and hardness of the contact surfaces, the properties of the oxide film covering the blank surface and the lubrication oil are the key factors that determine the friction
The radiation factor between the blank and tools is calculated by Eq. (4)

We selected the following properties to study: tensile strength, static tensile modulus.
The fillers addition into a polymeric matrix can significantly improve many operational properties.
Dependence of PCM modulus of elasticity from the absorbed radiation energy: ▬ – F4К20 ▲ – F4UV5DM3 One of the factors that affect the mechanical properties is ability to structure conversion under mechanical loads.
There is a correlation between changes in the PCM supramolecular structure and strength properties. 4.
Structure and properties of less filled polytetrafluoroethylene, J.

The vibration transfers to the bed of grinding machine and affects the precision of machining.
Many studies on the vibration of spindle systems have been carried out by analysing different kind of property indexes.
The parameters in the equations above can be obtained from NASTRAN, while the stiffness and the damping of the bearings which are closely relative to the structure, preload, lubrication, vibrations and other factors of the bearing.
Altintas, A General Method for the Modelling of Spindle-Bearing Systems, Journal of Mechanical Design, NOVEMBER (2004) Vol. 126 /1089
Janota, Simulation of dynamic properties of a spindle and tool system coupled with a machine tool frame, International Journal of Advance Manufacturing Technology ,DOI 10.1007(2011)s00170-010-2917-7

Influence of Morphology on the Rheological Behavior of Semi-Solid A356 Aluminum Alloy Zhang Henghua1,a, Zhang Xiannian1,b , Shao Guangjie1,c , Xu Luoping 1, Yang Yitao1 and Sun Baoliang2 1 School of Material Science and Engineering, Shanghai University, Shanghai 200072 China 2 Shanghai HuiZhong Automobile Manufacture Ltd Company, Shanghai 200122 China a hhzhang@mail.shu.edu.cn, bxiannzhang@163.com, cgjshao@staff.shu.edu.cn Keywords: Aluminum alloy, Semi-solid slurry, Morphology, Apparent viscosity Abstract: The morphology of semi-solid alloy is one of the key influence factors on the rheological behavior of slurry during die filling and the mechanical properties of formed parts.
Introduction The semi-solid forming (SSF) technique has been widely applied in many industries, especially in the automobile industry, after more than 30 years research and development since the technique had been invented at 1970s as it has the advantages of more compact microstructure, less entrapment of gas and better mechanical properties [1~4].
The microstructure and morphology of semi-solid alloy will greatly affect the rheological behavior of slurry during die filling and the mechanical properties of formed parts [5~7].
Only a few papers have studied on the controlling microstructure and morphology by mechanical stirring [8].
Cyprus Sept. 20-23 (2004) [8] Tang Jinglin, Zheng Daben: Influence of Microstructure of Semi-solid A356 Alloy on its Transient Rheological Behavior, Special Casting & Nonferrous Alloys, Vol. 20 (2000), p.43 [9] Zhang Xiannian, Zhang Henghua, Shao Guangjie, Xu Luoping: Development of Viscometer for Semi-solid Metals, Special Casting & Nonferrous Alloys, Vol. 25 (2005), p.425 [10] Zhang Henghua, Tang Xuan, Shao Guangjie: Microstructure and Mechanical Properties of Purity Aluminum Refined with Salt Containing Ti and B Elements.

Several searches have been conducted in the past, and continue to be until the present time to improve the parameters affecting the effectiveness of the composite patch repair.
The material properties of the 2024-T3 aluminum alloy plate, the Carbon/epoxy composite patch and the FM-73M adhesive are regrouped in table 1.
Table 1 Material properties.
The subscript p is used to distinguish properties of the patch composite.
Sih, Handbook of stress-intensity factors.

In this paper, in order to evaluate the mechanical properties and reliability of structure, a systematic testing program is proposed, which includes the applied load, data acquisition, data processing.On the base of testing data, evaluating of the condition of the bridge through using comparative analysis method.
Analysis of Static Load Test Results The Efficiency of Static Load Test According to Bridge Engineering Testing Manual, the load efficiency factor should be between 0.95 and 1.05.
Therefore, the load test can reflect the construction stressing properties of the bridge which is under the city-A level car load.
And this structure is good in the mechanical properties and restoring elasticity ability.
Conclusion Through the bridge for testing, can be learned, operational status of the bridge to ensure its safe use, with the rapid development of China's transportation construction, a substantial increase in traffic volume, traffic density and vehicle load increases, these factors have led to a lower carrying capacity of the bridge, and even affect the safety of operations, Therefore, the comprehensive assessment of carrying capacity of the bridge is particularly important.