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On the down-side, it can affect dimensional accuracy by causing subsurface damage and introducing residual stresses.
As regards the structure of the part to be machined, the relationship between processing, structure, properties and behavior of a material is extremely important because it is known that this structure, which depends on how it is processed, exerts a high influence on the properties of the obtained products and their performance depends directly on these properties [9].
Thus, castings have mechanical properties that depend on aspects of its structure, such as grain size, dendritic, lamellar or fibrous spacing, and defects such as heterogeneities in the chemical composition, size and shape of inclusions, porosity, which in turn is a function of the conditions of solidification and, therefore, affect its mechanical properties [9].
With the increasing demands of modern industry for materials with enhanced properties and better ease of mechanical forming, controlling the kinetics of the solidification process of metals and alloys comes every day consolidating itself as an object of study of extreme importance to obtain materials with homogeneous properties and increasingly suitable for practical use.
On this way, considerable research [10-19] have been made ​​in recent decades in order to establish in a systematic way the influence of various operating parameters and thermal phenomena involved in the solidification on the resulting structure, seeking to raise the mechanical properties and therefore, the performance of the materials solidified by experimental procedures which were implemented in the vast majority of directional vertical upward and downward solidification systems.

The physical and chemical properties of mustard oil are investigated.
However, the detoriating petroleum reserves and the damaging environment have made the scientists to look out for alternative fuels for the diesel engine without affecting its fuel economy.
Variation of Smoke emission with loads Hydrocarbons The emission of Hydrocarbon in the diesel engines is due to factors such as, wall deposit absorption, oil film absorption and crevice volume etc.
After determining its properties, by varying the compression ratio, its emission characteristics were studied in the internal combustion engine.
Srinivasa Rao, Performance and emissions of C.I.engine using blends of biodiesel and diesel at different injection pressures, International journal of applied research in mechanical engineering. 2(2012) 2231-5950

Introduction As a result of high mechanical properties like ductility and machinability [1], NCI is one of the widely-used cast iron types in the automotive industries.
Several factors can influence the property of the NCI during solidification.
Considering its broader application in the industries and susceptibility to pore formation during casting, a better understanding of the principles and factors affecting the volume changes could help one to control the micro defects.
References [1] ISO/TR 10809-1:2009, Cast irons -- Part 1: Materials and properties for design
Liping, Effect of Ce-Mg-Si & Y-Mg-Si Nodularizers on the Microstructures & Mechanical Properties of Heavy Section Ductile Iron, J. of Rare earths. 32(2014) 738–744

Introduction Nitrile-Butadiene Rubber (NBR) has good mechanical properties and abrasion resistance, particularly it has been used as a generic oil resistance of rubber, and it’s widely used in automotive, aerospace, oil and mining industries [1].
NBR is the random copolymerization of butadiene with acrylonitrile (ACN), the mechanical properties and oil resistance enhanced, cold resistance dropped with the content of ACN increased.
NBR with high acrylonitrile content, such as DN-219, N-32, shows good oil resistance and mechanical properties and their low-temperature properties can be improved by adding additives or chemical modification.
They both can improve the mechanical properties of the coating, especially the phenolic resin can improve the cold resistance in some way.
The NBR cured with composite curing system possessed best physical mechanical and cold resistance properties.

The existence of burr will not only affect the match of parts, but also reduce the dimensional accuracy and surface quality of the work piece.
Mathematical model targeted with burr and surface roughness based on the main experimental factors of cutter diameter, cutting depth, spindle speed and feed rate.
Experimental studies indicate that these main factors affect burr generation [4].
It is found that the cutting edge radius, the run-out of spindle and feed per tooth are key factors in the study of micro milling mechanism.
Construction and property analysis of NC micro milling machine system [D], Nanjing: Nanjing University of Aeronautics and Astronautics, 2007.

Rock Bolting Numerical Simulation Research and Application of The Face Breakthough You lin Xu 1,a, Hui Zhang 2,b, Wei Zheng 3,c 1 Beijing Mining Research Institute, China Coal Research Institute, Beijing, 100013, China, 2 Faculty of Resources & Safety Engineering, CUMTB, Beijing 100083, China, 3 Mining College of Guizhou University, Guiyang , 550003 a xuyoulin2006@163.com,b caikuangzhang@163.com,c zhengweicaikuang@126.com Key words: Breakthough, Simulation, Stress field, Prestressed Abstract: This paper analyzes the importance of rock bolting in coal mining, and the difficult of using rock bolting in breakthough with the affect of mining, adopt hydraulic fracturing and coal-rock mass strength test methods to test the seam stress and rock strength.
Figure 1 4109 Roadway layout plan Figure 2 Histogram comprehensive roadway rock Support Stress Field Analysis The coal-rock mass strength, structural and integrated stress field is the three elements of engineering coal-rock mass, there is necessary link and relevant between them[1]. under the interactions and influence between the three elements, showing coal rock mass mechanical properties, deformation and failure characteristics. the coal-rock mass’s stress change under the influence of the mining is the main factors of the destruction of deep coal-rock, it is more likely to appear coal rock mass power damage phenomena like coal and gas outburst, rock burst and so on in depth coal mines.
For time, the in-Situ rock stress field appear first, then have the mining stress field and rockbolting stress field; For space, the in-Situ rock stress field exists in the crust, the mining stress distributes in the area which affected of extractive activities, while the rock bolting stress field distributes in smaller bolting area.
Numerical model used Moerkulun model, physical and mechanical parameters of coal rock mass show in Table 1.
Table.1 Physico-mechanical parameters of coal and rocks Parameter Coal Roof Mezzanine Floor r(kN/m3) 14 24 25 13.4 Young’Modulus(MPa) 2400 3100 3600 2600 Poisson's ratio 0.33 0.3 0.3 0.29 0.26 Compressive strength(MPa) 20 30.6 83 17.6 Tensile strength (MPa) 0.49 2.3 2.3 8.1 Cohesion (MPa) 2.7 4.8 4.8 2.5 Friction angle (°) 28.1 32 32 44 August 2010, the researcher use the hydraulic fracturing method to test the geomechanical of two measuring points.

Interface diffusion is strongly affected by ultrafine crystallinity and incorporated defects.
Introduction Fundamental knowledge of diffusion properties of ultrafine grained (UFG) materials prepared by severe plastic deformation (SPD) is one of the central issues in their potential technological applications [1].
Severe plastic deformation is known to affect the grain boundary (GB) diffusivity [2, 3, 4, 5].
The penetration profiles were determined by parallel mechanical sectioning by means of a precision grinding machine and weighing the sections using a microbalance.
Admittedly, triple junctions where the non-equilibrium GBs meet, may also exhibit enhanced diffusion properties.

Mechanical properties of models made with this technology depend on the orientation on the working platform [10].
In this way, it is possible to design models with different mechanical properties and viscoelasticity.
These parameters affect the energy density transmitted to the sintered layer that has a major effect on both the mechanical properties and the quality of the surface [16], and the accuracy of the microstructure.
Proper selection of these parameters allows one to obtain the desired mechanical properties with high accuracy and reduced time of the manufacturing process.
A common feature and also the first step in the manufacturing prototypes by additive technology is a 3D model designed in CAD software and saved in a "stl" file, which significantly affects the quality of components as well as on its mechanical properties.

These alloy properties are desirable requirements to be integrated in hot formed components.
In addition to these experimental results, thermodynamic calculations were done with help of the JMatPro software in order to analyse the effect of Mn and C on the resulting mechanical properties as a function of the quenching rate.
An important aim of this process is to obtain specific mechanical properties in selected areas of the manufactured components [1,2].
Mn is an alloying element which additionally offers the possibility of increasing hardness and other mechanical properties.
Bleck: Analysis of microstructure and mechanical properties of different hot stamped B-bearing steels.

The essence of influence mechanism is effective body energy Ev and specific filling rate ω, and can be used as critical process factors.
Laser absorption rate is a key factor affecting heat input.
Laser power, scanning speed, wire feeding speed and surface roughness are selected as changing factors, and the width, height and dilution rate of the cladding layer are selected as evaluation criteria for molding quality.
(2) Effective body energy Ev and specific filling rate ω can be used as critical process control factors.
Laser surface treatment of multicrystalline silicon for enhancing optical properties[J].