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However, if the more rolls are located near the rear stands, the more the surface quality of the hot strip products is affected by their surface morphology.
Discussion As described in the introduction above, hot rolling properties are greatly influenced by various microstructural factors such as: (1) kind, shape, volume fraction, and distribution of carbides and graphite; (2) characteristics of matrix; and (3) solidified cell structure.
In summary, these microstructural factors should be systematically controlled to optimize the all related mechanical properties, when manufacturing CRIC rolls with excellent rolling performances.
The report [10] revealed that, some of V can be dissolved in the matrix, so it strongly affects the formation of graphite due to its relatively high affinity with carbon.
The number of the NbC carbides is increased by increasing the Nb contents, but if Nb contents exceed eutectic line PQ, there will be a density-induced NbC segregation zone which appears at the outer region of the section. 3) The roll-4 seems to be reasonable in terms of correlation between microstructure and rolling performance, but it needs to increase the spherical graphite by 3~5% through suitable adjustment of microstructural factors.

Aging Behavior of Aluminum Alloys after Severe Plastic Deformation Zenji Horita Department of Materials Science and Engineering, Faculty of Engineering, Kyushu University, Fukuoka 819-0395, Japan horita@zaiko.kyushu-u.ac.jp Keywords: grain refinement, precipitation hardening, severe plastic deformation, equal-channel angular pressing, Al-Mg-Si alloys, Al-Si-Ge alloy, Al-Ag alloy, transmission electron microscopy, tensile properties Abstract.
The microstructures are observed using transmission electron microscopy and the mechanical properties including hardness are measured.
ECAP is conducted on these alloys and subsequent aging behavior is examined in terms of microstructures and mechanical properties.
Whereas the effect is minor on the specimens without ECAP, aging significantly affects the level of flow stress including the shape of stress-strain curve for the specimens subjected to ECAP.
It is concluded that the 100-hour aging is the optimum condition for the enhancement of the tensile stress as well as the uniform elongation: the improvement in the tensile stress is a factor of 1.5 when compared with the solution-treated specimen without ECAP while keeping a similar level in the uniform elongation.

Introduction During the process of hot rolled steel plates, the control of austenite grain size plays an important role in microstructure optimization and property improvement.
This must influence the mechanical properties of hot rolled steel plates [1].
Especially in thermomechanically controlled process, the amount of deformation, deformation temperature, strain rate and interrupted time are important factors to affect the austenite grain size.
Severe plastic deformation, i.e. higher amount of deformation, is also a key factor to refine austenite grain size, even to refine final microstructures.
All the compression tests were carried out using a thermo- mechanical simulator.

Figure 1.The Plate Rolling Equipment Diagram This process not only improved the property of production, but also reduced yield losses of the rolling mills.
Cross rolling can be affected by the time of the billets and staying temperature, and the length of the awaiting temperature of plates, the finish rolling and each section of rollers in different rolling stages and other factors.
The Optimal Allocation Plate Model and Algorithm The optimal allocation Plate Model Rolling quality optimized model:Suppose that is a date vector for each attribute of the plate after rolling (such as thickness, width, toughness, ductility, briquettability, mechanical properties and so on). , is the th attribute,, is the total of attributes.
(2) Mutation operation: Mutation operation is the key step in the differential evolution, defined as (2) Where, is randomly selected from the current population, ,andare individuals randomly , selected from the population.is a zoom factor
Research on Product Configuration Optimization Based on Multi-object Genetic Algorithm [J], China Mechanical Engineering, 2004, 15 (20):1819-1875

In these assemblies the stress field is complex and a number of parameters, including effect of the geometrical discontinuities, contact between elements, tightening, material properties and applied load must be considered.
Fretting is the degradation of near-surface material that arises from a triple interaction among wear, corrosion and fatigue phenomena [2], often observed in nominally-clamped mechanical assemblies subjected to oscillatory loads or vibratory excitation.
In this case, the initiation of the fretting fatigue crack is affected by a number of factors, such as the shear stresses τrθ, contact normal force, contact friction, etc.
However, such an increase in fretting fatigue life cannot be observed because fretting fatigue is also affected by the contacting pressure, which accelerates the surface damage of the material [2]
Normally, the second factor is more important than the first.

Wan2 1College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China. 2Chengdu Aircraft Industrial (Group) Co., Ltd, Chengdu 610092,China.
The perfection of tool is the key factor to guarantee the forming quality of composite parts.
In order to get higher surface precision, using composites, whose property especially the thermal expansion coefficient is close to composite part’s, to make the tool, can eliminate size error and deformation in the heating and cooling process[1-4].
The last, in the forming process, the temperature of the moulding board changes constantly and each point of the moulding board has different temperature, the part don’t cure synchronously, affecting the quality of the products.[5-6].
The heat-conducting property and the structure of the tool, will influence the distribution of the temperature of the composite part.

Manufacture of large and homogenous bulk pieces and wires for electro-mechanics, has posed a great challenge, due to the opposition between the poor mechanical properties of ceramics and the requirements of shape and working.
This thermal gradient produces thermal expansion unstabilities which affect to the distance between the sample and the Hall probe.
In the pictures we consider only a thin sheet of material so introducing a high shape factor that produces some convexity in the magnetic flux density distribution.
º2 the factor is just 1.95.
The current distribution is also affected by the field existing on the environment, produced by other conductors as in cables.

(6) where ωm is the mechanical angular speed, Nph is the number of turns per phase, Kwn is the winding factor, Bpk is the amplitude of airgap flux density, D is the airgap diameter, L is the motor axial stack length, and Ipk is the peak phase current.
Motor with 18-slot/16-pole configuration is selected due to highest winding factor and to reduce the effect of cogging torque.
It shortens the magnetic flux pathway and allows the maximum magnetic properties of stator core during the motor operation without permanently magnetized it.
This is calculated based on the 0.9 T amplitude of airgap magnetic flux, 100 mm motor axial length, 106 mm airgap diameter, 120 number of turns per phase, 0.960 winding factor, 750 rpm motor angular speed, and 10 A peak phase current.
The motor performance is affected by adjusting stator tooth width nearly to the saturation level of the stator core hysterisis level.

Similar to the mechanical properties, their dissolution rate is also depending on the composition.
This natural mineralization has been adopted to produce ceramics and/or coatings with unique mechanical properties [60].
During film deposition, the structure of the film forms rapidly (as compared to bulk structures) and is influenced by several complex factors.
Bioactive glass ceramics: Properties and applications.
Bioactive metals: Preparation and properties.

The problems of actual production the motor’s noise and vibration can also be solved. 1.3 Determine the properties of model materials The core structure of vehicle synchronous motor is a combination of the orthotropic silicon layers, which can not do as uniform continuous elastic body do.
Normal lamination plane ​​of elastic modulus is difficult to value, which affected by Core is a whole piece or slice punching, laminating coefficient, whether painted.
The overall is orthotropic, we assumed winding and the stator teeth keep in close contact when modeling, but in fact the stiffness of windings is much lower than copper, on top of this, the issues of slot fill factor also should take into consideration.
Material properties are shown in Table 2.
Tab. 1 Material properties of stator Property Steel Laminate structure Cooper Chassis Windings ρ/(kg/m3) 7800 6960 8900 2650 3045 E2=E3/Pa 2.058e11 2.058e11 1.2e11 2.0e11 9.5e10 E1/Pa 2.058e11 1.5e11 1.2e11 2.0e11 1.4e10 G13=G23/Pa 8.0e11 7.3e10 4.6e10 7.6e10 4.6e9 G12/Pa 8.0e10 8e10 4.6e10 7.6e10 5.4e9 ν12=ν13=ν23 0.28 0.3 0.3 0.3 0.3 1.4 Solving and post-processing Stator core assembly can ensure the quality of the grid by Sweep of refined mesh networks, etc.