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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.

Studies on microstructure and property of material of SiCp/Gr/ mixed and reinforced aluminum-based composites prepared by semi-solid pouring method Zhiyong You a, Zhuo Wang b , Lifeng Hou cand Ying-hui Wei d Taiyuan University of Technology, College of Materials Science and Engineering, Taiyuan, Shanxi, 030024, China ayouzhiy1486@163.com, bwangzhuo19860531@163.com, choulifeng78@126.com,dweiyinghui@tyut.edu.cn Keywords: SiCp, Graphite, Aluminum-based composites, mechanical property, damping capacity Abstract.
In addition to the low prices of both SiCp and Gr, the relative high intrinsic damping of Gr particle in the composites can improve its damping capacity and SiCp can enhance its tensile strength and damping capacity, thus the adoption of SiCp/Gr mixed and reinforced aluminum-based composites can improve its mechanical properties and damping capacity at the same time[5-7].
Many documents have stated that the method can affect the growth of dentrite adversely and has reinforced particle uniformly distributed in the alloy melt[9], therefore, the experiment adopted the semi-solid stirring and gravity pouring method and aimed at preparing reinforced aluminum-based granular composites with excellent mechanical properties and damping capacity.
The author suggests that dislocation damping and interfacial damping are the most important factors as for the composites.
Metal Matrix Composites: Mechanisms and Properties.

Working Parameters Selection of Bladder-type Accumulator Under the Different Conditions Xiaoming Wu1，a, Yanfang Yang2，b 1,2The Department of Mechanical and Electrical control Engineering, Yanshan University PR China axmwu@ysu.edu.cn, byyf3052008@163.com Keywords：accumulator; working parameters; poly index; different conditions Abstract Currently there is a lot of material presented on the selection of different conditions and specific formula in order to select accumulator parameters.
Accumulators have a wide variety of applications in hydraulic systems because of their very useful properties.
Various factors of influencing on working parameters 1) The influence of poly indexr In the charge process of accumulators, the gas index is uncertain.
There are two factors affecting the gas heat release.
This paper looks the rate of increase pressure as the main factors affecting the poly index[3],[4].

Effects of Process Conditions on Properties of Nano-Magnetic Fluid Bing Chena, Yuguang Fanb School of Mechanical Engineering, Xi’an Shiyou University, Xi’an 710065, China abchen@xsyu.edu.cn, bygfan@xsyu.edu.cn Keywords: Nano-Magnetic Fluid; Coprecipitation; Orthogonal Design; Process Condition Abstract.
Table 1 shows the factors and levels in the orthogonal experiment.
Level factors of Q1, Q2, Q3 and Q4 stand for the total sedimentation rate of four levels.
Magnetic fluid magnetic curve Conclusion Influential factors on the properties of Fe3O4 magnetic fluid are system reaction temperature and adding speed of NaOH solution, according to analysis of orthogonal experiment.
Holding time and the pH value of coating sodium oleate are little effect on the magnetic fluid properties.

Introduction Owing to high hardness, outstanding wear resistance, excellent intermetallic friction resistance and corrosion resistance properties, nickel-base self-fluxing alloy powder has been widely applied to laser cladding process to strengthen the surface of many kinds of products.
Ji et al. [1] analyzed the reaction mechanism between metallic powder particle and laser and discussed the main influencing factors on quality of cladding parts and then presented effective ways to improve the quality of cladding parts.
Qiu et al. [4] researched the microstructure and properties of cladding coating by means of micro-analysis and mechanical property testing.
The substrate material is 45 steel which is a kind of improved carbon structural steel. 45 steel has excellent comprehensive mechanical properties after hardening and tempering treatment.
But the layer power could affect layer width to a large extent.

The goal in this work is to build a multivariate linear model to predict tensile strength since is one of the most significant mechanical properties of carbon-black reinforced rubber blends.
This model is based in the relationship between the final mechanical properties and the material composition, with the advantage of using this model to improve the design of the composition of the blend.
Introduction Commercial rubbers are a complex mixture of very different components, where each of these components takes to affect in the final physicochemical properties of the rubber blend.
Several techniques like data pre-processing, outlier detection, analysis of variance, analysis of covariance, analysis of correlation, multivariate data visualization, and Principal Components Analysis (PCA) are applied to study the influence of each composition variable in the output mechanical properties and to finally select the most significant variables to perform the most accurate models.
However following the explained methodology two important factors for model validation are improved.

The influence of contact states on dynamic properties of combination samples is analyzed based on the dynamic stress-strain curves and accumulative strain curves.
The practice indicates that the contact state between the bedrock and the concrete of the bottom structure is one of the critical factors which affect the service performance of the tunnel bottom structure.
Their major physical and mechanical properties are listed in Table 1.
On the premise of keeping the original properties of the rock samples, which were cut into two different types of cylindrical specimens with 15×15 cm and 15×12.5 cm (diameter×height) respectively.
Y., etal.: Experimental Research on Dynamic Properties of Coalmining Wastes.

Literature[7] ignores various factors, uses the following simplified formula: (1) λc is heat transfer coefficient, unit is W/(m.oC);T is temperature, unit is oC. 2).Heat capacity C0 and mass density Heat capacity refers to required quantity of heat when the unit mass object temperature elevates one-degree, unit is J/kgK or J/kgoC.
Concrete heat capacity is mainly affected by the aggregate types of concrete, mixture and moisture, but little influence, so heat capacity formula given in the general literatures do not consider these factors.
Meanwhile, loading geometric properties and material properties and initial conditions of onto the model, define distribution in fire condition for transient temperature field analysis, analysis of time is 5400s, step number is 200[2], obtain temperature field distribution in the above figure.
Structural stress analysis in fire Based on the actual simply-supported bridge fixed method, beam ends sets mechanical boundary conditions.
Fig.6 Thermal deformation in fire According to mechanical analysis request, loading corresponding geometric properties and material properties and initial conditions of reinforced concrete model onto the model, define condition for mechanics analysis, analysis of time and step number as same as temp-erature field analysis, obtain simple supported beam deformation in the figure above.

Material is easy to attach scraps and to generate hardening phenomenon during manufacturing processes, simultaneously the tool life will shorten greatly and drilled quality like surface roughness will also be affected.
Table 1 Experimental parameters Parameters Conditions Materials Mar-M247 Haynes-230 Inconel-718 Feed rate (mm/min) 100 125 150 Speed (rpm) 3600 4800 6000 Experimental material properties Ni-based superalloys mostly applied in military and aerospace industries; major application includes aerospace motor, steam turbine machine, high temperature heat treatment equipment, environmental protection incinerated machine, chemical industrial equipment, airplane turbine leaf, missile engine, nuclear energy generator parts and others thermostable, Bears dives changes equipment [1].
The chemical and mechanical properties [2] are shown in Table 2 and 3: Table 2 Chemical components Alloy Nickel base alloy Material Haynes 230 Mar-M247 Inconel 718 Composition WT(%) WT(%) WT(%) Cr Co Mo W Ti Al Fe C Si Ta Hf La B Nb S 22 5< 2 14 - 0.3 3< 0.1< 0.4< - - 0.02 0.015< - - 8.25 10 0.7 10 1 5.5 0.5 0.15 - 3.3 1.5 - - - - 17~21 1< 2.8~3.3 10 0.65~1.15 0.2~0.8 17 0.08< 0.35< - - - 0.006< 4.75~5.25 0.002< Ni ~57 ~59 50~55 Table 3 MAR-M247, Inconel-718, Haynes-230 mechanical properties Properties (room temp) Value MAR-247 Inconel-718 Haynes-230 Ultimate Strength (MPa) 965 1375 860 Yield Strength (MPa) 815 1100 390 Elastic Modulus (GPa) 205 － 211 Hardness (HRC) 38 22 12 Results and Discussion Bush length comparisons after drilling This study tries to explore friction drilling using three different materials such as MAR-M247, Inconel-718, Haynes-230 under different drilling condition spindle speed
From above three results that we can see that different spindle speed, feed rate could have significant impacts on the strength and mechanical property of Ni-based superalloys after thermal friction drilling.
Figure 8 Comparison of simulation and real friction drilling result (Haynes-230) Conclusions This study applied thermal friction drilling to conduct experiments selecting three materials such as Mar-M247, Haynes-230 and Inconel-718 Ni-based superalloys using different spindle speeds and feed rates to form a bush length of workpiece and obtain hole surface roughness , axial force, and drill wear to see the different features, from the result of the experiment shows that material strength and mechanical features are the most significant factors and the conclusion as follows: 1.Inconel-718 is a high strength material, so the destructive and yield strength is the highest of three materials.

Grinding wheel wear, grinding temperature, and vibration are main factors affecting job quality and machining efficiency.
In grinding process, primary effect factors of grinding force are grinding depth and feed rate, and the grinding depth is variable on CNC tool grinder.
In Fig.4, E, EC and ∆u are grinding force error, error change rate and controlled value, respectively. ke, kec are quantizing factors, while ku is scale factor.
Force response shows that the dynamic properties are good and the force will reach steady state in 1~2 s when grinding depth changes suddenly.
Force response also shows good dynamic properties.