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A New Method of Characterization on Microstructure of Casting Alloy Zheng Liua, Xiao-mei Liub Faculty of Mechanical and Electronic Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China a liukk66@163.com, b liuxm66@163.com Keywords: A356 alloy, fractal dimension, primary phase, morphology, casting Abstract.
Introduction There are the great effects of the morphology of microstructure in casting alloy on the forming ability and the mechanical properties, in which one of the microstructural characteristics in casting alloy with good forming properties has certain amount of particle-like microstructure [1].
At present, shape factor is a more accurate analysis method to quantitatively describe the phase morphology in metallic material [2].
During formation and growth of primary phase, because of affecting by preparing condition and external physical field (for example pouring temperature, isothermal holding, ultrasonic or mechanical disturbance, addition of modifier and so on), there will be change on the morphology, size and structure for primary phase 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 primary phase morphology in the casting alloy, in which they are nonlinear in essence.

The forward algorithm is used to predict the structure response for a set of supplied mechanical input properties whereas the reverse algorithm is able to derive the elastic-plastic and/or creep properties from the measured deflection curves.
Cheng found that, for a sharp indentation, a given set of basic mechanical properties can determine the essential features of the structure response, whilst the reverse problem is not unique [15].
Determine elastic-plastic properties.
As the elastic-plastic properties are quite different for each material and temperature, the elastic-plastic properties should be included when the database is built.
[14] ISO, NPR-ISO/TR 29381, Metallic materials – Measurement of mechanical properties by an Instrumented indentation test – indentation tensile properties (ISO/TR 29381: 2008, IDT) [15] Cheng, Y.

One limit to their performances is serious residual stresses [3], which adversely affect their properties as fatigue, fracture, corrosion, friction and wear resistance [4].
The ultimate residual stress ascribes to two parts influenced factors.
This phenomenon shows that the structure and thermal mismatch is the main influence factors.
The main factors that affect the thermal stress were the structure and thermal mismatch.
Guo: Handbook of utility thermal physical properties, chapter, 21, Beijing: Chinese Agriculture Mechanical Press (1986) (In Chinese)

They found that oil supply pressure do affect static and dynamic performances of journal bearing.
Details of test bearing dimensions, lubricant properties and operating parameters are given in Table 1.
This is as expected likely due to many of the actual factors during the bearing operations were not considered in the numerical and computational models.
Oil groove location was found to affect the torque.
Oil groove locations have affected the frictional force.

These factors significantly reduce their service life, which forces to costly repair work.
In the present study, the authors proposed a combined technology of applying coatings by the method of “cold” gas-dynamic spraying followed by surface treatment with a laser beam, which leads to an increase in the operational properties of coatings.
As shown by previous studies, the substrate material does not significantly affect the physicochemical properties of coatings formed by cold spray method, therefore, the coating was formed on economical steel St3.
Here there is a deep heat-affected zone, and the laser beam tracks are clearly visible.
Yurkov, Structure and properties of the bronze-based functional coating obtained by gas-dynamic and microplasma spraying.

These properties are strongly related to the microstructure obtained during thermo-mechanical processes.
The alpha content is affected by the temperature of deformation and the morphology of the alpha grains is influenced by the strain and strain rate.
The control of the alpha phase (hcp) morphology in wrought alpha + beta titanium alloys is of great importance in achieving desired combinations of static and dynamic mechanical properties.
The shape factor decreases with increasing strain (Fig. 4b), meaning that alpha grains become more elongated by increasing the strain.
Quantitative analysis for deformation at 930°C: a) area distribution and b) shape factor distribution of the alpha grains for different strains.

Research on the Influence of Cutting Fluids on the Critical Depth of Cut in Diamond Cutting of Optical Glass BK7 Ming Zhou1,a , Peng Jia 1,b and Min Li 1 School of Mechanical and Electrical Engineering, Harbin Institute of Technology, Harbin, P.R. of China, 150001 a Zhouming@hit.edu.cn, bhunter@hit.edu.cn Keywords: Diamond cutting, Optical glass, Critical depth of cut, Cutting fluid Abstract.
In diamond cutting of optical glasses, the magnitude of critical depth of cut for brittle-ductile transition is an important factor affecting the machinability of the work material in terms of production rate and surface quality.
In this work, scratching tests with increasing depths of cut were conducted on glass BK7 to evaluate the influence of the cutting fluid properties on the critical depth of cut.
The objective of this research is to evaluate the influence of the cutting fluid properties on the critical depth of cut.

Such properties can be obtained using magnetic iron oxide nanoparticles.
The considerable length of the pipelines and rather stringent conditions for their operation require increased attention to the isolation of the surface from the effects of external and internal factors leading to corrosion wear.
Since most composite materials are used in aviation, space technology, and mechanical engineering, great importance is attached to the uniformity of the distribution of properties in the entire volume of parts.
In the solid-state, it is necessary to provide increased mechanical properties.
The use of nanoparticles made it possible to increase mechanical properties and increase mobility and penetration [17-19].

Total energy of underwater explosion can be regarded as the effective energy explosive.The mian idea of study the relationship between formulation and energy output structure,is to increase the total explosion energy based on reasonable distribution of shock wave energy and bubble energy. 2.2 The technical approach of underwater powerful explosives The formula design of underwater powerful explosives is a very complicated subject.It does not only include the research on energy structure properties by underwater explosion,but also involves many subjects such as mechanics, chemistry,physics,charging process and cost.There are many problems which remain to be researched.In this paper,we study of explosive energy.And the technical approachs of underwater powerful explosivesidentified we used in underwater weapons described as follows: (1)The loss of explosive energy increases with the increase of explosion pressure.The improvement of explosion heat is increased the output energy of explosion.Therefore
(2)The detonation mechanism of aluminized explosive shows that the oxidation reaction of aluminum powder obviously increase the decay time constantof of underwater explosion shock wave and reduce the explosive blast and decay rate of energy density.The kinetic characteristic of aluminum powder is one of the important factors that affected the underwater explosion shock wave characteristics[4]
(3)To ensure the mechanical properties of explosives,sensitivity,charging technology and economy and other performance,a way of improving the energy is to reduce the mixed explosives inert binder or switch energetic blender[5].
Aluminized explosives and explosive energy design with meso system components are also closely linked,such as Al powder particle size,surface area and other factors affect meso explosion heat,detonation pressure, detonation velocity and energy of wavefront consumption.Charge density and the charge process also have a significant impact on the structure of energy output of aluminized explosives.Therefore,for the design of aluminized energy explosives,it should be calculated on the basis of repeated theoretical repeated experiments,in order to obtain a good overall performance for explosives[6]. 2.3 Formula design Explosive JULH-1 is made up of RDX as its main explosive,AP as its oxidizing agent,Al as its raw materials and HTPB as its binder.Making the raw materials to micor order or sub-nanometerorder by ultrafine grinding and using the technology of grain composition,several experiments of measuring energy output structure were carried out under water and some scientific and reasonable
The ultrafine technology is introduced to JULH-1,in which part of RDX and ammonium perchlorate processed by ultra-attenuation,particle size reach micron or sub-nanometer.Contrast the explosion energy,JULH-1 output shock wave energy,bubble energy and the total energy is much higher than the domestic popular explosives of Underwater Ordance in the main charge of TNT,RS211,THL,etc.Because the surface of RDX explosives were significantly increased after super fine crushing,an explosion reaction, the reaction speed accelerated, the energy loss in the process of detonation decreased.The ultrafine ammonium perchlorate can improve the physical structure, mechanical properties of explosive mixture and accelerate the detonation reaction speed,reduce the energy loss in the water,can effectively improve the water energy output, improve the level of the explosive power[7]. 4.

After a detailed analysis of the materials used in idlers technologies, we considered that their properties could be improved if we cover them with thin layers but with high properties.
We want to improve the idlers mechanical properties and the materials selection for the substrates was made after documentation in specialty literature, standards and manufacturers catalogues.
The deposition parameters are variable [3], and influences the quality of the coatings and mechanical properties as well.
Appropriate sensors and design solutions have to be adopted to observe the main affecting parameters of fretting.
Barca., Gears materials analysis in order to establish the mechanical properties, Bulletin of the Pollitechnic Institute of Iasi, Romania., (2010)