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The microstructure evolution during the extrusion process of AA6XXX aluminum alloys is getting a significant interest from extruders and researchers because of the effect of the grain structure on the extruded component properties.
Because there are so many affecting elements, it is extremely challenging to forecast the microstructure evolution and, as a result, research activities are still required to understand and control the aluminum alloy recrystallization behaviour.
The microstructure of these profiles, defined as the arrangement of crystals, grains, and phases at the microscopic level, plays a lead role in determining their mechanical properties, formability, corrosion resistance, and overall quality [5-7].
Material Properties AA6063 Density [Kg/m3] 2690 Specific heat [J/kg K] 900 Thermal conductivity [W/m K] 200 Thermal expansivity [m/K] 2.34*10-5 Young’s modulus [GPa] 68.9 Poisson’s ratio 0.33 Fig. 2.
Given the substantial influence of numerous process and metallurgical factors on the final grain size, as well as the complexity of the extruded geometries and the limitations associated with the chosen measurement methodology [10] for experimental grain dimension analysis, the ± 25% error range, which was similarly adopted by Donati L. et al. in [10], is regarded as indicative of good prediction accuracy.

The combination of concave model cavity shape, rivet size and sheet metals has been proved to be one of the key factors affecting riveting molding.
The orthogonal experiment table with 3 factors and 5 levels is designed in order to gain matching scheme of rivet and sheets, including 50 groups of experiments.
Rivet, top sheet and bottom sheet are taken as experiment factors.
The traditional method of inspecting joint quality is to measure joint mechanical properties through experiments.
In conclusion，punch velocity is one of the important factors which affect the joint quality of SPR of half-hollow rivets.

From this study, it was found that different types of lubricant affect the wear progression and friction coefficient during a sliding movement.
Lubrication can be used in an engineering system without replenishment and is an important factor in increasing the lifetime of mechanical components.
Material and Method The pin-on-disk machine is a laboratory apparatus used for measuring friction and wear properties (ASTM G99).
This is one of the reasons why increasing normal pressure is a major factor contributing to the wear rate.
Coefficients of friction are further factors that contribute to the wear progression of the pin.

However, the factors that affect the machined surface residual stress are various and complex.
The tool geometry parameters are illustrated in Table 1, and the mechanical properties are shown in Table.2.
Fig.2a shows that the average cutting force is about 200N, and it reveal that that basically prestress conditions hardly affect the cutting force.
The surface topographies are observed via a 3D Super Depth Digital Microscope System (KEYENCE VHX-500FE) with an enlargement factor of 500.
Figure.4 represents the microstructure of chips under different prestress condition, the photographs are captured by a SEM with an enlargement factor of 200.

The factors such as the fitness between tool and toolhoder, the length of oil chamber bulge, oil pressure and rotation speeds are analyzed in the paper, the results can offer some effectively guidelines and reference for toolhoder machining and processing quality control.
Fig.6 Analysis results when a force F is applied Fig.7 Radial stress figure when a force F is applied Effect of fit clearance.The fit clearance affects not only the change of the clamping length, but also affects the change of the contact stress between chuck and tool.
Relative to the above two factors, the oil pressure has little effect on the radial grip clamping rigidity.
The factors such as different oil, length of the oil chamber bulge, different fit clearance and different rotation speed are analyzed to the effect on chuck grip rigidity.
The following conclusions can be drawn: （1）In the four factors, the speed of the chuck is the most obvious factor to rigidity, and the rotation speed will lead to larger swings on tool so affects the surface quality

Introduction Yttrium aluminum garnet (Y3Al5O12, YAG) is one of the most developed materials as laser host and phosphor due to its optical properties and its uniqueness when doped with another materials.
The formation of YAG phase require such a high temperature at 1600oC which is costly and will result in the microstructure coarsening adversely affect its properties [5].
This shows that mechanical activation thru milling process can affect the morphology and the powders distribution significantly as the other works too [12], [13], [15].
Bučevac et al., “Effect of YAG content on creep resistance and mechanical properties of Al2O3-YAG composite,” Ceram.
Wang, “Synthesis and mechanoluminescent properties of submicro-sized Y3Al5O12:Ce3+ particles,” Chem.

The contribution of the transient temperature field is also temperature-dependent thermo-physical properties as shown in Fig. 2.
Structural Analysis For mechanical analysis, the temperature history of each node from the preceding thermal analysis is input as the node load with temperature dependent mechanical properties shown in Fig. 4.
For the plastic strain component, a plastic model is employed with the following features: the Von Mises yield surface and temperature-dependent mechanical properties.
Fig. 4 Thermo-mechanical properties of SS400 steel as a function of temperature.
U.Dar: International Journal of Advances in Mechanical Engineering, 2009

Die Casting Process Simulation Analysis .There are many factors that affect the quality of the die casting.
The worse the mechanical properties and the effect of casting filling are getting.
Therefore, these factors equal errors.
The casting filling effect and mechanical properties are good.
When pouring temperature is above 630℃, the temperature will be the main role on the shrinkage and grain coarsening when thermal expansion and contraction, With the pouring temperature increased, the filling effect of the castings and mechanical properties of the worse.

On the contrary, the dimensionless parameter is sufficiently sensitive to a fault slewing bearing, it is not influenced by some factors, such as type of slewing bearing, rotational speed and loading.
Non-stationary signal usually contain more abundant information than the stationary one, so the information of the non-stationary signal may reflect more properties of the system[3].
The local properties of non-stationary signal need to be represented by using both the method of time domain and frequency domain, which is called as time-frequency domain analysis for vibration signal.
This method also has the property of reducing noise.
Friction torque are affected by many factors, such as the structure, designation, processing, friction, lubrication, the Fig. 5 Picture of friction torque testing Fig. 6 Temperature curve in accelerated life testing working conditions, etc.

And droplet formation, size, transition mode and droplet behavior are very important factors for affecting weld seam forming, welding quality and overall performance.
The Influence of Magnetic Field on Mechanical Properties.
Lin Zong analyzes the influence of longitudinal alternating magnetic field on mechanical properties of magnesium alloy welded joint [27].
The results reveal that welding current is 60A, magnetic field current is 2A, magnetic field frequency is 20Hz, the mechanical properties of weld joint are achieved the best value, the hardness is 76.2HV, tensile strength is 231MPa.
The interaction of the waveform of exciting current as well as the phase between welding current and exciting current on arc shape, droplet transfer, microstructure and mechanical properties of the weld joint is not fully clear.