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This material is remote from the weld and has not been deformed, although it may have experienced a thermal cycle from the weld, but it has not been affected by the heat in terms of microstructure or mechanical properties as shown in Fig. 10a
It is possible to correlate these welded regions with variations in mechanical properties.
The same dependence of tensile shear strength on tool holding time and tool rotation speeds can be realized in terms of both microstructure factors , i.e. the (dn) and (tu) sizes.
Nogi, “Effect of Tool Shape on Mechanical Properties and Microstructure of Friction Stir Welded Aluminum Alloys”, Materials Science and Engineering, PP. 25-31, (2006)
Qu, “The Influence of Pin Geometry on Bonding and Mechanical Properties in Friction Stir Weld 2014 Al Alloy”, Materials Letters, PP. 2948-2952, (2005)

In detail, a spiral tool path is given to the tool, after the sinking phase with the aim to enhance the final joint mechanical properties [12].
This model is used to investigate the distribution of temperature, strain and strain rate in the heat affected zone and the weld nugget during the sinking stage.
Then a heat affected zone (HAZ, C) is reached, in which material has undergone a thermal cycle which has modified the microstructure and the mechanical properties.
A constant shear friction factor of 0.46 was used for the tool-sheet interface on the basis of a previous experimental thermal characterization and of a numerical sensitivity analysis for the shear friction factor m performed for butt joints [14].
The grain dimension is in direct proportion to the inverse of the Zener-Holomon parameter, which in turn, as known, depends from the temperature, the strain rate and the CDRX activation energy constant Q [13]: )exp(RT Q Z • = ε (2) The present model, through a proper subroutine, is able to predict the Z parameter distribution, giving important information about the final microstructure of the joint and thus its mechanical properties.

Because the triaxial stress degree and maximum tensile stress are a main factor deciding the occurrence of the ductile fracture.
When corresponding parameter of the material reaches the critical value, the material begin to ductile fracture.Due to the ductile fracture relating with material properties, history of deformation, and processing parameters etc, selecting a reasonable critical value to predict occurrence of ductile fracture is necessary for the specific process of ductile fracture.
Conclusion In the process of plastic forming of metals, ductile fracture can make the material produced unnecessary waste on the utilization and economy, and is an important factor affecting the forming limit of metals to improve seriously.
Ruan: China Mechanical Engineering.
Shima: Journal of Mechanical Working Technology.

Context and motivations Thanks to its electrical properties, silicon carbide (SiC) is considered as the material of choice for high power and high temperature electronic devices while mechanical properties make it very attractive for Micro-Electro-Mechanical-Systems (MEMS) applications [1-3].
As a consequence, the impact of the thickness towards the mechanical properties of thin (< 1µm) 3C-SiC epilayers could be detrimental and seriously affect MEMS functioning.
This ratio is the leading property for any resonators, enabling to achieve higher resonant frequencies and better quality factors [13].
Influence of structural defect on the mechanical properties of 3C-SiC First, the mechanical properties of thin 3C-SiC layers (≤ 500nm) grown on silicon have been explored through the analysis of static and dynamic behavior of cantilevers.
Indeed, these authors suggested that the mechanical properties of 3C-SiC epilayers could be affected by the defect density.

As result of recent developments, these materials can be produced with various electrical, thermal and mechanical properties according to their intended purpose [1-5].
It is important to assess the effects of the various environmental degradation factors on the tracking and erosion performance of the material in use.
EXPERIMENTAL RESULTS 1- VIRGIN TESTED SAMPLES: The virgin tested samples were evaluated in the fog chamber to provide reference data for comparison with samples, which were subjected to the various degradation factors.
Organic materials degraded by environmental factors could either enhance leakage current and accelerate tracking or cause erosion failure.
Hence, inorganic fillers are incorporated into the polymer materials to enhance mechanical and electrical properties in addition to minimizing the effects of tracking and/or erosion.

A classification method based on the concept of topological quantity is proposed to investigate the heat affected zone (HAZ) and the center of the weld metal zone (WMZ).
The right combination of human factors and machine conditions, such as: heat pattern, speed and power can give good to excellent structure homogeneity during welding process.
Tables 1 and 2 show the chemical composition and mechanical properties of the materials.
Mechanical properties of the specimens Yielding stress (MPa) Tensile strength (MPa) 318 440 (a) WMZ weld seam structure.
Justyna Rozwadowska, Department of Mechanical Engineering, Kyushu University, Japan for her feedback about the observations.

Their application makes possible mass reduce, load capacity increase, improvement in the mechanical properties when it is possible.
Aluminium-magnesium alloys present good mechanical properties at moderate mechanical efforts (400 to 700 MPa) and good corrosion resistance.
The Al-Mg alloys have special attention due, not only to the lightness of the material, but also to certain mechanical properties and reciclability.
Such alloys cause good mechanical properties in moderate mechanical efforts (400 to 700 MPa) and good resistance to the corrosion [1-5].
The mechanical properties of the Al-Mg-Nb alloys, in laboratory scale [10], are very superior to register for most of the aluminium alloys.

Microstructure and Properties of TiAlN/AlN Composite Film Deposited on Cam's Profile by Ion Beam Sputtering Technique Peiquan Guoa, Shouren Wangb and Huanyong Cuic School of Mechanical Engineering, University of Jinan, Jinan, China, 250022 a oss_guopq@ujn.edu.cn, bme_wangsr@ujn.edu.cn, cost_cuihy@ujn.edu.cn Keywords: TiAlN/AlN film; ion sputtering deposition; microstructure; micro-hardness; cam Abstract.
The microstructure and properties of TiAlN/AlN composite film deposited on the profile surface of cam (made of 45 steel) by ion beam sputtering deposition were discussed.
X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscope (TEM) analysis has been used to characterize film's microstructure and properties.
The aim of this work is to examine the morphological, mechanical, corrosion resistance and wear resistance properties of them.
The substrate bias is one of the most important factors for determining micro-hardness value.

According to the analysis results, the higher residual stress and the highest concentration of hydrogen are distributed in and surround the heat affected zone (HAZ), and vary with different humidity.
HE is a very complicated process that can affect virtually any metal or alloy and is nearly always unpredictable, few pages or even books would not be enough to fully describe it [2, 3].
(4) Where Q is the energy input rate, ff and fr are the fractional factors of the heat deposited in the front and rear quadrant, a, b, cf and cr are heat source parameters.
Rate-independent elastic-plastic constitutive equation is considered the von Mises yield criterion, temperature dependent mechanical properties and linear kinematic hardening rule.
(5) where {Dd} is divided into {Dde} for the elastic range and {Ddp} for the plastic range, {c} is a parameter to reflect the stress increment due to the dependence of the physical and mechanical properties of the material on temperature, {dσ} is the stress increment, {dε} is the strain increment and dT is the temperature increment.

The aim of this study is to show the excellent mechanical properties of the composite wires, and the contact relationship between the mechanical and other properties (i.e. thermoelectric power) and the possibility of their standardized production.
So it was also worth trying other metals as matrix materials to see any existing differences in mechanical properties.
The other factors needing consideration were the handling properties (castability, fluidity, etc.)
After these factors had been considered, it was tin that was chosen as the matrix metal, owing to its low melting point (232 °C) and good fluidity.
General conclusions are that composite wire reinforcement improves the mechanical properties of specimens.