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(2) Dep. of Aerospace and Mechanical Engineering, University of Notre Dame, USA
Illustration of the three-layered polymer-coated steel used in the experiments There is significant flexibility in formulating this material, and many combinations of chemical and mechanical properties can be achieved.
The Surface Quality Factor has been defined as: 0.
Representative examples of these Surface Quality Factors are given in Fig. 2.
The inserts were produced by diamond polishing, but were not refinished for the subject research in order to save time and expenses; it is felt that surface quality factors of 8 could probably be improved with better tool surface finish.

For better understanding the effect of compaction factors, all the test specimens in his research have the air voids around 7% and the heterogeneity index was defined as follow: (2) Where M is the total number of vertical layers; Vi is the air void content in the ith layer and VAvg is the overall average air void content of the specimen.
Effect of Aggregate Grading on Air Voids Distribution Aggregate grading is one of the most influential aggregate characteristics and affects almost every important property of asphalt mixture including stiffness, stability, durability, permeability, workability, fatigue resistance, frictional resistance and resistance to moisture damage [19]. 
The CA ratio is the ratio of the fine part (interceptors) to the coarse part (pluggers) of the overall coarse aggregates and has significant effect on asphalt mixture volumetric properties and compactability [20].
The particle-particle contact between aggregates is a key factor in the force transmitting inside asphalt mixture.
With the help of coordination number, the force transmitting paths between aggregates can be quantitatively studied, which is very helpful to evaluate the pavement performances, like the permanent deformation, fatigue cracking, low-temperature cracking, moisture susceptibility, and friction properties of Hot Mix Asphalt pavements.

Mechanical properties of titanium alloys are strongly interlinked with their microstructures developed during thermomechanical processing and final heat treatments [10].
Step cooling in furnace was affecting the growth of α lamellas and precipitating secondary α-platelets.
Elshaer, Microstructure and mechanical properties of cast and heat treated Ti−6.55Al−3.41Mo−1.77Zr alloy, Transactions of Nonferrous Metals Society of China, vol. 23, (2013), pp. 3517-3524
Zeng, Crack initiation and mechanical properties of TC21 titanium alloy with equiaxed microstructure, Materials Science & Engineering A, vol. 586, (2013), pp. 215-222
Yao, Microstructure and mechanical properties of TC21 titanium alloy by near-isothermal forging, Transactions of Nonferrous Metals Society of China, vol. 25, (2015), pp. 72-79

In this study factors influencing the rates of emission of Acoustic Emission (AE) signals from propagating fatigue cracks were investigated.
Tables 1 and 2 outline the chemical composition and mechanical properties of the test material.
Table 1: Specified Chemical composition of 2014 T6 aluminium material Si Fe Cu Mn Mg Cr Zn Ti V Zr 0.82 0.18 4.40 0.71 0.59 0.05 0.04 0.01 0.01 0.00 Table 2: Mechanical properties of 2014 T6 aluminium material Yield Strength (MPa) Ultimate Tensile Strength (MPa) Mean 439 492 Fatigue tests were performed on a servo hydraulic test machine under constant amplitude loading with a frequency of 2 Hz and stress ratio of 0.1.
As in figure 3, Stages 1, 3 and 4 can be discerned, albeit with the hit rate significantly increased by a factor of 10.
AE Hit rates were significantly less than in figure 3 by a factor of 100 for crack lengths less than 25 mm.

The activation volume can be expressed as ** ln τ γ ∂ ∂ = & kTv , but it is common to plot * ln v MkT ≈ ∆ ∆ ε σ & (σis the stress,ε& is the strain rate, M is the Taylor factor) as a function of σ.
Stress relaxation The stress relaxation tests consisted in interrupting the sample loading during a mechanical test (in compression in the present study).
The mechanical tests were carried with a MTS/20 machine.
The results indicate that the metal properties are not strongly affected by the strain history.
Calculation of the strain rate sensitivity, m , from a log-log plot of the stress as a function of the strain rate measured during creep testing in nano indentation. 3≈= fsnHK σ , the constraint factor is the ratio of the hardness measured by nanoindentation ( MPa Hn 1500= ) by the flow stress of the material measured in a macroscopic mechanical testing ( MPafs500=σ ) [6].

Introduction Flexible Asphalt pavements face multiple distress forms during their service life due to traffic loading and environmental factors.
Asphalt Binder Properties.
Zycotherm Properties.
Rheological Properties Dynamic shear rheometers (DSRs) are used to measure the rheological properties of asphalt binders.
A review of the warm mix asphalt (WMA) technologies: Effects on thermo-mechanical and rheological properties.

These mechanisms are depend on sheet thickness, laser beam dimensions, scanning speed and physical properties of irradiated material [1].
Several studies have been carried out in order to investigate the relationship among the process parameters, the mechanical and thermal properties of the material, the material-source interaction and the final geometrical properties, such as the bending angle of the sheet.
In order to reduce the number of experimental tests, a mixed Taguchi orthogonal array L-16 with three factors, has been selected, as summarized in Table 1.
Orthogonal array L16 with three factors used in the experiments.
As shown by MEP, all the experimental factors were found to have significant influence on production time as confirmed by analysis of variance (ANOVA).

Recent studies have showed that their morphology had a strong influence on their optical and electrical properties.
The reports showed that both shape and size of the MNPs were key factors determining incoupling efficiency.
Gurunathan, Silver Nanoparticles: Synthesis, Characterization, Properties, Applications, and Therapeutic Approaches, Int.
Maier, Optical and Structural Properties of Ultra-thin Gold Films, Adv.
Huo, Poly(acrylic acid)-stabilized colloidal gold nanoparticles: synthesis and properties, Nanotechnology 21 (2010) 455702 [13] C.

Meanwhile, we selected elastic-plastic mechanical model and incremental theory to analyze the problem. 1.1 Establishing heat source model Because the hot spread quickly in metal, highly concentrated heat source was used to transfer much more heat to workpiece in an instant and causes time-variation and unsteady characteristics during welding. we selected realistic model of normal heat considering materials’ physical properties changes with temperature[3].
Assuming the distribution of heat is Gaussian normal distribution function, then integrates the equation is: （1） （2） （3） Where: q—effective heat power, J/s； k—heat concentration factor,1/mm2； r—the distance between a point within the circle heat source and the center.
Therefore, judging from thermal expansion and contraction properties of the metal, different parts of the weldment will get different temperatures, and will lead to different thermal expansion.
However, the materials thermal expansion close to molten pool affected by mental around gets deeper than that away from weld seam, which will result in the materials In the weld and around subject to relatively large compressive stress.
Temperature Field of Thick Welding Process, Three-dimensional Finite Element Numerical Simulation of the Stress Field[J],Chinese Mechanical Engineering,2001,12(2):183~186

The effect of Zr and Ti doping on the structure and mechanical properties is demonstrated.
It has now been well-established that the determining role in the attainment of anomalous properties of nanomaterials is played by their internal interfaces [7].
As the rule of mixtures cannot adequately predict the mechanical properties of ultra-fine multifilamentary composites, special strengthening mechanisms should be worked out for them, taking into account the presence of interfaces and matrix-filament compatibility.
Effect of doping on the structure and properties of Cu-Nb composites Doping is one of the main ways of improvement of properties of various materials, e.g., it is widely used for an enhancement of current-carrying capacity of multifilamentary Nb3Sn-based superconductors [49].
We compared the structure and mechanical properties Cu-18Nb and Cu-18Nb-0.2Zr composites processed by Routes A (1 intermediate annealing) and B (3 intermediate annealings) described in the previous section.