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It is well known from previous research that zirconium (ZrO2) has good mechanical properties, stable at high temperatures, resistant to high corrosion, thermally resistant and inert to chemicals.
Zirconia is utilised in dental biomaterials due to its mechanical properties and bio-compatibility [15][16].
Various factors may affect the percentage variation of this element; i.e., weather and surrounding environmental conditions.
[6] Z. hai He et al., “Recycling hazardous water treatment sludge in cement-based construction materials: Mechanical properties, drying shrinkage, and nano-scale characteristics,” J.
Mo, “Zirconia Based Dental Biomaterials : Structure , Mechanical Properties , Biocompatibility , Surface Modification , and Applications as Implant,” vol. 2, no.

Speed Control System Design of Winding Mechanism For Composite Films Y.H.Du1, a , X.M.Jiang 1, b and G.Y.Yang 1, c Mechanical & Electronic Engineering College, Tianjin Polytechnic University, China a duyuhong@tjpu.edu.cn, b jiangxiuming@tjpu.edu.cn, cyanggongyuan@tjpu.edu.cn Keywords: Winding Mechanism, Ratio Control, Mechanical Model, Control Strategy.
In addition, the imbalance of tension will result in the offset and drift, and thus the quality is adversely affected[3].
ds JJJJ ++= 303 (2) According to the winding material properties, the moment of inertia Js is: 44 330() 2 s rbq Jrr π =− (3) where Js is the equivalent moment of the composite films; ρ is the composite films mass density of unit width; q is the space factor; r 3 is the radius of the winding shaft; γ is the proportion of the composite films; g gravity acceleration; b is the width of the composite films.
With these strategies, the dynamic property is improved and the tension is stabled.
Through industrial applications, it is demonstrated that the developed system has the properties of structural compactness, high automation and reliability.

High Al low C - Mn steels are attracting growing interest because of their unique mechanical properties.
The major efforts in studying these steels are focused on the effects of heat treatment routes on the final properties.
To comply with customer demands, these products should not only possess the right combination of mechanical properties resulting from controlled TRIP-effect, but should also have satisfactory weldability, surface quality and coatability.
Both Si and Al increase the thermal stability of the retained austenite in final products, which is crucial for mechanical properties.
Evidently, in case of AHSS the factors other than variations in MFS come into play that result in wide spread of the rolling force.

Some alloying elements, which tend to segregate, make the as-solidified dendritic microstructure prone to hot cracking and then require well-controlled cross-reductions during subsequent rolling or thermal-mechanical treatment to homogenize microstructure and get optimum properties.
The effect that an alloy's segregation behavior has on its final properties is the reason why semi-solid and post solidification hot rolling processing conditions are an important subject of R&D for innovation and refinement of industrial processes.
In all three cases, the casting process is followed by a hot deformation step, in particular hot rolling, to control the necessary geometrical, mechanical, technical and physical properties of the flat products.
The austenite grain size influences the hardening and softening behaviour of the slab material, while being simultaneously affected by the solute state of the as-solidified slab and related precipitation kinetics.
The laboratory simulation must take into account the mentioned factors and their influence on the deformation process in compliance with the characteristics of meting / solidification and then time-temperature-deformation cycles of the real process.

Poor ability to move the snarling in the drilling process in terms of small diameter holes frequently affects the tools ware and poor surface quality.
Key factors which determine tool life and hole quality are chips formation, burr formation, angle of cutting radius, coolant, point of cutting, machining conditions, angle of the tool, and peck drilling [1].
The burr formation depends on several factors such as the nature of the work piece material and cutting conditions.
The burrs can increase in proportion to the increasing properties of material ductility as well as the tool geometry [1].
Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology, 227(12), 1347-1355

Note: The numerical results are not directly transferrable to “real world” properties, because the inherent limitations of the atomistic method necessitate the use of unnaturally high strain rates (i.e. comparable to 1010 s-1 applied in prior studies [8]).
Nucleation of stacking faults, and dislocation interactions are also largely affected by localized defects or irregular GB structures [8, 11].
The visual results demonstrate that dislocation nucleation occurred on multiple slip systems that cannot correspond with the maximum Schmid factors, because only two maximum Schmid factor slip systems existed in this case.
Overall, this article concludes that the plastic deformation response in FCC metal polycrystals is influenced quite significantly by the presence of GBs, not as immobile barriers to slip, but as a consequence of complex elastic interactions affecting the slip systems of dislocations.
Suresh, Mechanical behavior of nanocrystalline metals and alloys.

Simulation of Microstructure Evolution Coupled with Fabrication Pressure for Two-Phase Ceramic Tool Materials Chuanzhen Huang1 , Bin Fang 1,2, Chonghai Xu 2, Sheng Sun3 and Hanlian Liu 1 1 Key Laboratory of High Efficiency and Clean Mechanical Manufacture, Ministry of Education, Center for Advanced Jet Engineering Technologies (CaJET), School of Mechanical Engineering, Shandong University, Jinan China, 250061 2 School of Mechanical Engineering, Shandong Institute of Light Industry, Jinan China, 250100 3 School of Material Science and Engineering, Shandong University, Jinan China, 250061 Keywords: Simulation, Hot pressing, Ceramic tool materials, Microstructure Abstract.
Introduction Since many properties of ceramic materials, such as mechanical, electronic, magnetic or chemical, are affected and even dominated by the specific grain structure which is formed during fabrication.
The hot-pressing technology parameters, including fabrication temperature, pressure and duration time, finally govern the mechanical properties of the ceramic tool materials.
However, it is very difficult to optimize the fabrication parameters for the desirable microstructure and mechanical properties by experiments because they are closely related to one another.
It is proper that the maximum fabrication pressure is given 30MPa according to the properties of ceramic powders and the current experimental equipment.

Therefore, getting the right elastic matrix in arbitrary coordinate system is the prerequisite to analyze the mechanical behavior of this metal.
This structure results in highly orthotropic material properties.
For the X2-Y2-Z2 coordinate system, according to the symmetry and the NBSCS’s properties (, , , ), six independent elastic constants can be obtained: They are elastic modulus E001 and E110, Poisson's ratio ν001-110 and ν110-110 and the shear modulus G001-110 and G110-110.
For the X3-Y3-Z3 coordinate system, because the NBSCS’s physical properties is different in three axes, there are a total of nine independent elastic constants in the elastic matrix.
Based on equation (8), the precision of elastic matrix will affect the elastic stress in strain loading, and thus affect the shear stress according to Schmid law, and therefore have effect on the slip rate (equation 23) and the evolution of the strain hardening(equation 24).

Domestic research starts late in diamond cutting tools, which constrains the development of diamond cutting tools in China, affects the market share and results in a big gap comparing with the world advanced level.
CVD diamond which is similar to natural diamond in properties can be used to make thin diamond film coated tools and brazing diamond film tools, which can be sued to machine auto parts. 2.2 Preparation technologies of diamond cutting tool materials The application of natural diamond cutting tools has a history of hundreds of years.
However, due to limited resource, higher manufacturing costs and other factors, natural diamond cannot fully meet current industry need, so a variety of synthetic diamond material emerges.
Synthetic diamond of large single crystal has the same excellent properties as natural diamond; we can achieve ultra-precision machining by using tools of this diamond material.
Nanometer diamond simultaneously has properties of nanometer materials and diamond materials, and as a tool coating material, it can improve efficiency and extend tool life.

It is known that dislocations, i.e., linear defects of the crystal lattice that violate the correct alternation of atomic planes, affect the processes of plastic deformation and fracture of materials under the influence of stresses.
However, dislocations affect not only the strength of solids, but also their electrical resistance, internal energy, optical, semiconductor, magnetic and other properties [1], determine the mosaic structure of real crystals, surface topography and the nature of crystal growth at small supersaturations.
Therefore, by tracking, through analysis of the characteristics of the propagation of elastic waves in a solid, the changes occurring with a dislocation microstructure, one can evaluate the mechanical properties of the material and also predict the residual life.
To create a model that takes into account the nonlinear elastic properties of the medium, it is necessary to analyze the behavior of the elastic fields of a dislocation near its axis, since this is a region with a high concentration of stresses.
Nonlinear Stationary Waves If the influence of dissipation on the evolution of wave processes in (6) is small BA→0, then, as a result of competition between dispersion and nonlinear factors, stationary waves can form in the system.