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At nanoscales, due to the increasing ratio of surface/interface area to volume, surface/interface energy plays an important role in the physical and mechanical properties of solids [1, 2].
However, the classical elasticity theory cannot account for the effects of surface energy on the mechanical performances of solids.
The numerical solutions of the dynamic stress concentration factor are graphically illustrated.
The effects of the incident wave frequency and surface elasticity on the dynamic stress concentration factors in the matrix material are analyzed.
For a larger value of s, the surface energy significantly affects the DSCF around the hole.

The experimental results show that the content of metastable tetragonal phase of ZrO2 and grinding stress are the primary factors which induce martensitic transformation on ZrO2 ceramics ground surface; during grinding the deeper the grinding depth is, and the bigger abrasive grain size is, the grinding stress in material matrix is larger.
Some studies indicated that phase transformation is also the key factor which affect the residual stress of ground surface[1][2].
Influence of grinding parameters on residual stress of nano-ZrO2 ceramics The residual stress of ceramics surface generated during grinding is the key factor to induce cracks.
Residual stress, acting as a key parameter of surface quality, its value and property affect the strength and reliability of precision ceramic parts greatly[3] [6].
Engineering ceramic materials Processing technology and its application [M].Beijing: Beijing mechanical industry press, 2008 [2] Tian Xinli, Yu Aibing.

The growing use of cast Al-Si alloys necessitates a more profound comprehension of its mechanical properties and the effect of processing factors upon the end product [3].
There is no doubt that the variety of Al-Si hardener phases affect its properties, especially its wear resistance.
Time and temperature parameters of the T6 treatment are very important factors towards controlling the properties of the alloys [15].
Therefore, T6 treatment used to improve the mechanical properties of alloy.
Large eutectic Al2Cu phase decreased the alloy’s mechanical properties [35].

However, most models show good results for Fe-C austenite without affecting the effect of alloying substitution elements.
However, most models show good results for Fe-C austenite without affecting the effect of alloying substitution elements.
The formula registers the dependence on the carbon concentration for the pre-exponential factor of the carbon diffusion coefficient (thermodynamic factor) and the effective activation energy of its diffusion (in accordance with the experimental data).
This allows further workpiece’s grinding without affecting the maximum concentration of carbon in the surface layer.
As a consequence, it does not affect the deterioration of the surface’s mechanical properties [9].

The results presented in Figure 3 enabled us to determine the mechanical properties of the studied material.
The mechanical properties drop in this phase that is to say that the mechanical behavior of the polymers is affected.
We deduct that the mechanical properties of the studied material (ABS) are influenced by temperature and the material tends to become more fragile.
Effects of thermal cycles on mechanical properties of an optimized polymer concrete. 
Mechanical and physical properties of epoxy polymer concrete after exposure to temperatures up to 250 ºC. 

Although the reinforce elements can improve the strength and stiffness properties, however the machining cost is high as reinforced PEEK is extremely abrasive.
Factors and levels Factors Levels 1 2 3 Rake angle (Deg°) 5 10 15 Clearance angle (Deg°) 6 8 10 Helix angle (Deg°) 20 30 40 No. of flute 2 3 4 Table 2.
Table 1 and Table 2 shown the factors and their levels and orthogonal design matrix respectively.
It shows that the dominant factor that affect towards machining performance is number of flute, followed by helix angle, rake angle and clearance angle.
Number of flutes is the most significant factor that affects the surface roughness value.

When an underground cavern goes through the layered rock masses, surrounding rock stability is not only affected by anisotropic mechanical properties of layered rock mass, but also by the intersection angle between stratification plane and cavern axis.
However, when cavern axis intersects the strike of stratification plane with a small angle or both are parallel, anisotropic mechanical properties of layered rock mass influence the cavern stability more.
According to lots of previous experience in physical model tests, similar material also has to meet the following principles [11]: (1) The main mechanical and deformational properties of similar material must resemble those of prototype material; (2) The mechanical and deformational properties of similar material are supposed to stabilize and avoid being affected by external conditions during test procedure; (3) Certain physical and mechanical properties can be adjusted through changing the mixture ratio to adapt to the requirement of similar conditions; (4) Physical models must be made and molded easily and can solidify rapidly, but when it solidifies, there is no big shrink; (5) It’s easy to paste testing elements on the surface of physical models; (6) Model material must be rich in sources and low-cost.
Therefore, the first thing is to find out which are the decisive factors among all of the influencing ones and only then will the similar material be selected.
(3)The stress distributions and failure modes of surrounding rocks of deep-buried layered rock mass are all similar owing to the influences of anisotropic mechanical properties of layered rock mass.

The improved properties of the nano-structured metals open up perspectives for their application in innovative industries such as aerospace, surface transport and biomedical implant manufacturing.
Introduction Lightness of materials can be defined in two basic ways: (a) in absolute terms by material densities and (b) in relative terms using so called specific properties.
In particular, Young's modulus and the yield strength are used as properties of interest and, accordingly, light materials can be ranked based on the ratio of modulus or strength to their density.
Among other factors, the effect of grain refinement down to nanometres has been examined in a number of metals and alloys [1-5].
The Hall-Petch equation is one of the most important empirical relationships describing the influence of microstructure on the mechanical properties of metals and predicts a linear dependence of the yield strength/hardness on the inverse square root of the average grain size, 1/(d) 1/2.

Since residual stress has effect on surface quality, dimension stability and operating life of parts, many scholars engaged in the research of factors that effect the distribution of residual stress [2-10] and obtained some achievements, but the research achievements in the field of simulation of residual stress involved in cutting titanium alloy thin-walled parts is still few.
Table 1 Johnson-Cook plasticity model coefficients of TC4 A [MPa] B [MPa] n C m 860 683 0.47 0.033 1.02 Table 2 Johnson-Cook shear failure model coefficients of TC4 d1 d2 d3 d4 d5 -0.09 0.25 -0.5 0.014 3.87 Material Properties.
The mechanical physical properties and thermal properties are listed in Table 3 and Table 4.
Because mechanical stress and thermal stress affect the residual stress simultaneously, the stress layer has no obvious increase from Fig.2.
Fig.6 The distribution of residual stress Fig.7 The deformation of work piece Conclusion (1) The distribution of the residual stress on the work piece surface is affected by the mechanical load and thermal load simultaneously.

It has been reported that by improving surface properties of coating layer the fixation of the bone to the implants can be enhanced [9].
Therefore, coating of stainless steel with biocompatible materials such as hydroxyapatite (HA, Ca10(PO4)6(OH)2) is an easy way to prevent corrosion of implants as well as improving the osseointegration properties.
Surface morphology of implant material is an important parameter which strongly affects cell attachment and protein adsorption [10].
Therefore size and volume fraction of the porosities are two important factors for osseointegration properties of implant materials Table 2 Data calculated by Image analysis software Sintering temperature ( °C) 600 700 800 Porosity volume fraction (%) 18.259 5.056 0.883 Porosity mean size (µm) 15 6 < 1 Therefore it can be concluded that HA coating sintered at 600 ºC shows best result for circulation of the body fluid although porous structure may result in lowering the mechanical properties of the coating.
Dahotre: Materials, performance factors, and methodologies, Materials Science and Engineering R Vol. 66 (2009), p.p. 1–70