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It was found that although the grain size is a prime microstructural parameter determining mechanical strength, second order factors such as grain size distribution and distribution of grain boundary misorientation angles also play a significant role.
Introduction Aluminium alloys play a key role in modern engineering due to their good corrosion resistance, relatively high mechanical properties and low weight [1,2].
For many industrial applications higher and higher mechanical properties are required, which in most cases exceeds the values possible to obtain by conventional coarse grained aluminium alloys.
All these microstructural factors will affect mechanical behaviour of UFG and nanostructural materials.
Only the sample after ECAP has a slightly worse combination of these properties.

Selected levels for input factors Input factors Level 1 Level 2 Level 3 Tool rotational speed (rpm) 300 400 500 Traverse speed (mm/min) 10 20 30 Tool plunge (mm) 2.7 2.8 2.9 All dimensions in mm Fig 1.
Grey relational grade plot of input factors level-wise Fig 3.
Yurzhenko, Structure and properties of the welded joints of single-type polyethylenes formed under the action of constant magnetic fields, Materials Science, 53 (2017) 186-193
Czigany, Effect of welding parameters on the heat affected zone and the mechanical properties of friction stir welded poly(ethylene-terephthalate-glycol), Journal of Applied Polymer Science, 125 (2012) 2231-2238
Shishavan and Richard Eungkee Lee, Mechanical properties of friction-stir-welded polyamide sheets, International Journal of Mechanical and Materials Engineering, 10 (2015) 1 - 8

Introduction Mechanical properties and microstructures change as nuclear power plant components are subjected to high temperatures and pressures over a long period of time.
The specimens were prepared by an artificially accelerated aging method in the laboratory, in order to investigate the degradation effects of CF8M on the mechanical property.
This phenomenon is considered to have a critical impact on mechanical properties.
The results of hardness, tensile and impact tests on dissimilar welded specimens disclosed that mechanical properties held by the HAZ of CF8M became the most vulnerable with an increase of aging time [11].
The reason for the reduced JIC value of CF8M base metal in comparison to that of HAZ was that the distribution of the ferrite phase on the HAZ of CF8M was concentrated in a relatively small area, thereby affecting the elastic-plastic fracture toughness value.

With the development of materials, the polyurethane as a new kind of high–performance material with its superior mechanical properties is widely used in marine engineering, ocean engineering and civil engineering.
Example design In order to research the mechanical properties of PFDSST members under axial compression, the author has divided all the members into four categories which are SPa, SPb, SPc, SPd.
(a) SPa (b) SPb (c) SPc (d) SPd Fig. 1 N–ε cures of four categories Influence factors Influences of hoop coefficient on mechanical properties of members.
Influences of slenderness ratio on mechanical properties of members.
Research on The Mechanical Properties of Polyurethane Filled Steel Tube under Axial Load.

Tracking Error Transform in Parallel Kinematic Machining Ghasem Amirian1, a , Christian Schenck 2, b, Bernd Kuhfuss3, c 1 Department of Mechanical Engineering, Yazd University, Yazd, P.O.BOX 89195 -741, IRAN 2,3 bime, Bremen Institute for Mechanical Engineering and Production Systems, Badgasteiner Str. 1, 28359 Bremen, Germany a gamirian@yazduni.ac.ir, bschenck@bime.de, ckuhfuss@ bime.de Keywords: parallel kinematic machining, contour error, tracking error, velocity gain factor Abstract.
These tracking errors are a significant factor that affects machining accuracy, beside geometric machine errors, vibrations, temperature changes and tool errors.
Contour errors originate as tracking errors in joint space are transformed by the forward kinematics and affect the tool centre point path in global coordinates.
Fig. 1: Simplified model of a cascade controller Radial Deviations in CKM and PKM Tracing a circle is a well established and easily applicable test to characterize static and dynamic properties of machine tools for inspection and acceptance purposes.
Conclusion Enhanced accuracy in parallel kinematic machining requires high performances of both the mechanical parts, especially in the joints with multiple degrees of freedom, and the machine controller.

Taghizadeh Armaky3,c J. sadeghi4,d 1 3Department of Mechanical Engineering, Islamic Azad University Ayatollah Amoli Branch, Iran 2 4Department of Mechanical Engineering, Babol Noshirvani University of Technology, Iran aj.bazrafshan@iauamol.ac.ir, bhamidgorji@nit.ac.ir, ctaghizadeh_ali@yahoo.com Keywords: Sheet Forming; Bending; Spring Back; Plastic Deformation Abstract.
This phenomenon will affect bend angle and bend curvature, and can be influenced by various factors.
The amount of spring-back/spring-go is influenced by various process parameters, such as clearance between die and punch, tool shape and dimension, contact friction condition, punch and die radiuses, material properties, sheet anisotropy, and sheet thickness.
Li X. and his colleges [3] showed that the accuracy of spring-back simulation is directly affected by the material-hardening model.
Table 1 shows the properties of the used Ck 45 sheet.

Further simulation and analysis affect of parts of structural changes on the damping characteristics.
Fig.4 Number of compression valves The thickness of the valves of the shock absorber is also an important factor of the mathematical model of the shock absorber, it can affect the working property of the shock absorber.
Measurement of Dynamic Properties of Automotive Shock Absorbers for NVH.
[5] R.Sonnenburg, A.Stretz, Dynamic properties of automotive damper modules.
Mechanical Systems and Signal Processing.

The base and brazing materials are C1220-O and BCuP-3S and their material properties are shown in Table 1 and 2, respectively.
Table 1 Mechanical properties of base metal Material Tensile Strength Elongation Melting Point 1220-O 195MPa 35% 1083°C Table 2 Mechanical properties of filler metal Material Solidus Point Liquidius Point Working Temperature BCuP-3S 643°C 720°C 720-815°C Filler metal Brazing gap z ro 7mm 0.05~0.12 mm Brazing Length Filler metal Brazing gap z ro 7mm 0.05~0.12 mm Brazing Length : Flow of N2-gas : Flow of Electric Control N2 Tank Main Controller Piping Specimen Cam Driving : Flow of N2-gas : Flow of Electric Control N2 Tank Main Controller Piping Specimen Cam Driving Fig. 1 Specimen of brazed joints Fig. 2 scheme of the fatigue test apparatus Life Test of Internal Pressure and Excitation.
Consequently, we used the orthogonal array according to DOE(design of experiment) which is the 4 level and the 2 factor, ( )2( 7L ).
Fig. 6 and Fig. 7 show the life distribution by the factors.
Ray: Mechanical Science and Engineering, A, Vol.383, No. 2, (2004), p.235-244 [4] P.

The physicochemical and physicomechanical properties of quick-setting compositions based on fine-grained electric steelmaking slag (ESS) produced by Izhstal PJSC, Russia, have been examined.
This can be proved by the obtained results of the setting and testing timing of the mechanical properties of the mixture.
It had a dark gray color and some large inclusions in addition to the silt part and demonstrated magnetic properties.
Results Chemical modifiers, including plasticizing admixtures and hardening accelerators, were added to the composition in order to improve its physical and mechanical properties: plasticizers – to increase workability and reduce water demand; accelerators – to shorten setting and accelerate hardening.
Mehrotra, Mechanical activation of granulated blast furnace slag and its effect on the properties and structure of portland slag cement, Cement and Concrete Composites. 8 (2008) 679-685

The singularity of the coarse as cast initial austenite grain size, combined with the limited total applied strain during hot working, requires a tailored design of the composition and deformation schedules in order to achieve the required mechanical properties.
These two aspects bring more and more difficulties as higher mechanical properties (significant additions of microalloying elements) and thicker final gauges (less total reduction) are required.
Both factors have been included in Eq. 2 to determine the time t0.5 [[] A.I.
In consequence, from the point of view of industrial practice factors affecting the Nb(C,N) strain induced precipitation kinetics need to be considered.
In those cases more attention must be paid to the rest of variables affecting Nb(C,N) precipitation kinetics.