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Fractal Characteristics of Microstructure in Semisolid A356 Alloy Zheng Liua, Xiao-mei Liub Faculty of Mechanical and Electronic Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, Jiangxi, China a liukk66@163.com, b liuxm66@163.com Keywords：semisolid; fractal; morphology; primary grain; A356 alloy Abstract.
The research has indicated that one of the structural characteristics in semisolid alloy with good forming properties has certain amount of particle-like primary grain in the alloy [1].
Discussion During formation and growth of semisolid microstructure, because of affecting by preparing condition and external physical field (for example pouring temperature, stirring power, stirring time, isothermal holding, ultrasonic or mechanical disturbance, addition of modifier and so on), there will be change on the morphology, size and structure for primary grain, at the same time, there is other change, included growth and migration of the grain, even fuse and separation of the grain to make morphology of the grain change.
There are the numerous complicated factors affecting the morphology during evolution of the primary grain morphology in semisolid A356 alloy, in which they are nonlinear in essence.

Performance of mechanical products depends largely on the parts surface processing quality, the failure of mechanical parts, usually starts from the surface layer; a good surface quality can improve the accuracy of parts, wear resistance, corrosion resistance and fatigue strength [1,3].
Due to the quality of PM60 mould steel after processing is affected by many factors, influencing factors of cutting process are complex, the fluctuating range of cutting parameters are relatively great.
Ltd., the workpiece size was 130 mm×40 mm×40 mm, the chemical composition of workpiece material is shown in Table 1, physical properties is shown in Table 2.
Table 3 Cutting factors level code table Factors Codes Levels 1 2 3 4 Spindle speed n( r/min) A 8000 10000 12000 14000 Feed speed vf (mm/min) B 300 450 600 750 Depth of axial cut ap ( mm) C 0.5 1 1.5 2 Radial depth of cut ae ( mm) D 0.15 0.3 0.45 0.6 Results and Discussions Response Analysis of Signal-To-Noise (S/N ratio).
The greater the value of variable factors explained the large fluctuations of the test.

Superduplex stainless steel alloy exhibit high mechanical and corrosion resistance, which main industrial application is in the petrochemical industry.
A good combination of properties is reached when the volumetric fractions of the ferrite (δ) and austenite (γ) phases are around 50/50 [3,4].
Welding in these materials is an important factor to be considered since the high temperatures achieved associated with a rapid cooling can alter volumetric fractions of the ferrite and austenite phases, as well as promote the formation of undesirable phases such as chromium nitrides, carbides, and sigma.
Low levels of ferrite (<25%) or high (>75%) may lead to decreased mechanical properties and corrosion resistance [5].
The microhardness measurement in welded joints is one of the main characterization techniques providing information of the hardness profile along the 3 zones, base metal (BM), heat-affected zone (HAZ) and fusion zone (FZ).

The experimental layout of L9 orthogonal array for the process parameters & tensile properties measured in terms of selected response variables is shown in Table 2.
Rejecting null hypothesis for feed rate suggest that feed rate is the most significant process parameter affecting multiple response characteristics.
ANOVA results considering grey relational grade as factor indicated that feed rate is the most significant process parameter affecting multiple response characteristics.
Kailas, Two-pass friction stir welding of aluminum alloy to titanium alloy: A simultaneous improvement in mechanical properties.
Pal, Fuzzy assisted grey Taguchi approach for optimization of multiple weld quality properties in friction stir welding process.

Environmental factors: Faced with the increasingly serious environmental pollution, the tubular belt conveyor can be used flexibly and conveniently in harsh environments areas or in the urban area, and plays an important role both on environmental and economic benefits while in Energy Saving through the major technology simulation and technological innovation.
The rigidity is the key factor to tube formation.
The tubular belt should have good elasticity, longitudinal flexibility in addition to the special structure design which needs to guarantee the tube has good flexibility when the two sides overlap with each other Each layer of tubular belt should have excellent physical and mechanical properties.
The related properties in different ratio of the compound can be read in Table 1.
In consideration of the glue formula, process conditions and so on factors have different degrees of impact on adhesion, to meet the use requirements of the adhesion between layer, we conduct a series of experiments.

School of Materials Science and Engineering,Lanzhou University of Technology,Lanzhou 730050,China Email:lanzhouxuyt@163.com Key words:Graphite;Molten Solar Salt;Hot corrosion;Graphitization degree Abstract: Solar Salt is the best hot transfer medium molten salt of solar thermal power generation.In order to study the hot corrosion behavior of four graphite is in the molten Solar Salt.The graphite immersed equipped with molten salt crucible placed in a muffle furnace,each period of time remove the sample and weight the weight gain until the sample is completely destroyed.The destruction forming of graphite is analyzed by XRD, SEM and OP.The study found that the order of hot resistant corrosion of molten Solar Salt of four graphite materials are the fine structuregraphite,isostatic graphite,9# graphite and cold pressing graphite.The principal factors can affect hot corrosion resistant of graphite is the graphitization degree.
Molten salt mixture properties in RELAP5 code for thermodynamic solar applications[J].
The preparation and properties of multi-component molten salts[J].
Effect of graphitization degree on the mechanical properties of C/C composites[J].Journal of Central South University of Technology (Natural Science),.2001,32(3):289-293
Effect of graphitization degree on properties of self baking carbon block[J].

The experimental scheme that a large number of factors are involved into needs to be rationalized and optimized with the Orthogonal design or Uniform design use conventionally by comparision with a small number of factors that usefactorial analysis[2-3].
In this paper, based on neural networks corresponding model of relationship between the laser machining parameters and surface quality was investigated and applied to predict the better combination of laser cutting design parameters for achieving optimum roughness. 1 Simulated Annealing and Neural Network The quality of laser cutting metal sheet has been affected by many factors including the laser properties, focusing lens properties, mechanical control systems, process materials and process parameters [4-6].
Because laser machining input parameters for optimization such as cutting speed, output power, gas pressure and other factors affected the quality of laser cutting for the existence of a variety of complex correspondence, which it was difficult to be explained from theoretical models and analysis.

For example, the organic polymer itself has a low dielectric constant, but the mechanical properties and thermal properties are poor, the adhesion force of which combined with the substrate is not strong, and to be unable to bear high temperature.
Through using different methods the low dielectric constants of PI film or particles are synthesized to have a variety of different structures and different properties, but the dielectric properties of prepared PI materials (including PI composites containing voids) still can’t reach the requirement of the development of electronics industry, and when the dielectric constant is reduced to 2.5 after the following the introduced void volume ratio of PI group is very high, resulting in the mechanical and thermal properties PI significantly reduced [9,10].
In addition, the mechanical properties and processing characteristics are the important parameters in determining the dielectric properties of materials.
A dielectric material for the large scale integrated circuit must meet the following basic requirements [18]: (1) a low dielectric constant with isotropic properties; (2) low moisture absorption; (3) excellent chemical resistance and heat resistance; (4) a good processing performance; (5) excellent electrical properties.
For example, add 0.5~2% of the ultrafine silica in PVC, it can obviously reduce the dielectric constant and dielectric loss factor. [19] The properties of low dielectric constant make the nanometer silica particles to be used for interlayer dielectric materials, which is widely used as a kind of dielectric materials with low loss.

In these applications, porous tungsten matrix with homogeneous pore distribution and high open porosity are important factors to obtain uniform infiltrates distribution, which has a significant influence on the performance of targeted materials [6].
Table 1 Physical properties of raw materials and classified tungsten powder.
Analysis of Microstructure and Properties of W-Cu Composites.
Zhang, Thermal and electrical properties of Cu composite produced by activated sintering, Mater.
Research on the Mechanical properties and microstructure of W-Mo-Cu Composites[J].

Introduction Gear is one of the most important components of mechanical products.
The quality of its design and manufacture will affect its performance directly.
Many factors can impact the reliability of gears because of complex structures and changeable conditions.
The Strength Calculation of Cylindrical Gear Pairs In reliability analysis, the uncertainty in a system mainly comes from two aspects, which are statistical and non-statistical factors.
Variations of material properties and boundary conditions and errors in manufacturing and installation lead to randomness of physical and geometrical properties of the structure.