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So, it has no stress concentration caused by machining micro mark during load bearing.Then the influence of nature, size, position,and distribution of defect on fatigue life was further analysed. 2 Experiment 2.1 Sampling Of Test Specimen Chemical composition and mechanical properties of E36 are showed in Table 1~2[4].
The specific dimension and sampling location of ultrasonic fatigue specimen are shown in Fig. 2.The specimens were machined and finally fine ground Table 1 Chemical composition of E36 steel（GB 712-2000） C Si Mn P S Cr Nb Ti Ni 0.18 0.10~.0.50 0.90~.1.6 0.04 0.04 0.02 0.015~0.05 0.02 0.40 Table 2 Mechanical properties of E36 steel（GB 712-2000） tensile strength Rm[MPa] yield strength Re[MPa] impact energy absorption Ak[J(-40℃)] Elongation Rate% A% 490~620 355 34 21 Fig. 1 Macrograph of welding jont Fig. 2 The specific dimension and sampling location of ultrasonic fatigue specimen 2.2 Test Process All the fatigue tests were carried out under the same constant amplitude load, Fatigue tests were conducted on ultrasonic fatigue tester (Fig. 3) with frequency of 20 kHz and stress ratio of R= -1, at room temperature.
The degree of different defects affecting fatigue life is largely different [5].
Nf [cycle] location of fracture crack initiation type of defect shape Size[μm] A [μm2] distance to surface [μm] 1 9.40E+08 weld joint pore solid type oval 2a=205.2b=126 20276.55 200 2 3.55E+06 weld joint pore solid type roundness Ø=400 125600 725 3 3.55E+07 weld joint pore solid type roundness Ø=110 9498.5 1000 4 1.38E+06 weld joint slag solid type oval 2a=615.2b=125 60346.87 0 5 1.87E+06 weld joint slag solid type oval 2a=341.2b=150 40173 171 6 4.73E+05 weld joint slag solid type rectangle L=1120,B=280 313600 0 7 2.76E+05 fusion line poor fusion face type rectangle L=37300,B=353 1316690 0 8 1.58E+05 weld joint surface crack face type 9 2.96E+05 weld joint surface crack face type 10 1.06E+09 no fracture 11 1.56E+09 no fracture 12 1.21E+09 no fracture 13 1.77E+09 no fracture Fig. 6 Stress nephograms around three kinds of pores (Ø -Diameter of pore; d- Least distance between pore and outside surface; Kt- Factor of stress concentration) 4 Conclusions 1 Specimens were sampled
Beijng: Standards Press of China,(1996 ) [5] Wu Liangchen, Fatigue properties of welded joints under ultrasound frequency component double loop load.

An analysis of the effects of particle size on surface segregation in Au-Ti alloy nanoparticles, with the alloy compositions Au90Ti10, Au50Ti50, is presented. 2.0 Thermodynamic Modeling of Nanoparticles The structure and the phase stability of nanostructure are constrained by the thermodynamics properties.
(6) The size of particles affects the compositional surface segregations due to the change in surface tensions caused by the variations in the number of broken bonds.
However, if the particle size exceeds 100 nm, the size effect is not pronounced to affect the surface segregation significantly. 4.0 Summary A thermodynamic model with the size effect incorporated was used to investigate the size-dependent surface segregation behavior of Au-Ti nanoparticles.
The size dependence of surface segregation and eventual phase separation may result in size-dependent properties of nanostructured materials.
Greer: in "Mechanical Properties and Deformation Behavior of Materials having Ultra- FineMicrostructures" Edited by M Nastasia, H Gleiter, NATO ASIA Series, Series E: Applied Sciences Vol.233 (1993), p.53 [7] R.Vallee, M.

The influence factors of the response time were researched.
There are two kinds of existing methods of focusing, 1) Ultrasonic energy focus by a piezoelectric ceramic transducer with a certain geometry (concave spherical surface) or through a solid lens, whose structure is simple but the focal length is fixed, so the only way to change the focal position is to adjust the place of the transducer using a mechanical method; 2) Ultrasonic energy focus based on the principle of phased array, which is to control the different initial states of each source unit to focus acoustic beam at the focal point.
The viscosity of the liquid material is an important influence factor to the response time of the liquid lens.
The thickness of the hydrophobic coating may also affect the response time of the lens system, as shown in Fig. 5.
Focusing Properties of Acoustic Fresnel Lenses [J].

The mechanisms are responsible for improvement of properties of modified material have been revealed.
The mechanical properties under study were hardness (Vickers method, PMT-3 device, Nanotest-100 nanohardness tester), bend and tensile ductility, and ultimate bending and tensile strengths (Instron-3369 testing machine).
Mondol’fo, The structure and properties of alloys, M.; Metallurgy, 1979
Bibik, Electron-ion-plasma treatment of Al-Si system: structure and properties, XX Petersburg Readings on the problems of strength, Part 1 (2012) 137 – 139
Nikonorov et al., Structure and mechanical properties of Al-Si (Ge) alloy under quenching and centrifugation of melt, Solid-state physics, V. 47, № 5 (2005) 886-892.

They are very different conceptually as PIMD can only calculate static properties whereas CMD and RPMD are designed to calculate dynamic properties based on different concepts from each other [30].
Undoubtedly, this model does not consider many specific factors affecting the diffusion parameters of atoms in a metal, such as the interaction of impurity atoms, the presence of vacancies, influence of the Debye temperature, quantum tunneling at a cryogenic temperature, etc.
From Atomic-Level Interactions to Mechanical Properties, Springer, 2022
Wipf, Hydrogen in Metals III: properties and Applications (Topics in Applied Physics, 73), edited by H.
Völkl, Hydrogen in Metals I: Basic Properties: 1 (Topics in Applied Physics, 28), edited by G.

In the past, fire caused heavy property loss and casualties in spacecraft [1, 2].
The performance of water mist fire suppression system may be affected by many factors such as droplet size, water flow rate, water mist velocity, ventilation condition, combustion reaction characteristics.
Under the influence of the above two factors together, the water mist concentration changes slightly.
As for the effect of the water mist velocity, the performance of fire suppression is affected slightlyin microgravity.
ASME 2004 International Mechanical Engineering Congress and Exposition, Heat Transfer, Volume 1, 2004, 489-492

Table 1 summarize the thermo-mechanical properties of the utilized alloys.
Materials thermo-mechanical properties Properties AA6016-T6 AZ31 Density 2.7 g/cm3 1.77 g/cm3 Poisson’s ration 0.33 0.35 Elastic modulus 69 GPa 45 GPa Tensile strength 250 MPa 290 MPa Yield strength 120 MPa 220 MPa Elongation 17 % 15 % Hardness 159 HV 138 HV Thermal conductivity 167 W/m°K 96 W/m°K Thermal capacity 0.89 J/Kg°C 1 J/g°C Results and discussion Experiments were conducted with the same materials and process parameters used for the simulations.
In turn, for the poor joint, the bonding line is a curve starting from the RS, close to the bottom of the joint, and ending in the AS close to the joint top surface. this is due to the different thermo-mechanical properties of the two materials.
It is worth noticing that the compression conditions obtained because of the material flow indicted by the tool are, together with the needed temperature conditions, the key factors for effective solid bonding to occur.
Jahazi, Microstructure and tensile properties of friction stir welded AZ31B magnesium alloy, Mater.

Zhang Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, 100 Ping-le Yuan, Chao Yang District, Beijing 100022, China a email: weisun@bjut.edu.cn Keywords: Al-Ni-Rh alloy, defect, crystalline approximant, electron microscopy, HAADF, HREM Abstract.
Since structural defects in a crystalline material have a great influence on its physical and mechanical properties, understanding the structural features of those unique defects in structurally complex alloy phases is therefore an important issue to be tackled.
In comparison with the traditional HREM imaging, the contrast of which is affected by many factors such as sample thickness, defocus values, etc., HAADF-STEM imaging is chemical sensitive and directly correlated with the atomic number of each constitutional element.
A HAADF-STEM image can therefore be interpreted directly without the need to consider those factors affecting the HREM imaging.

It is efficient, rapid and accurate for solid, liquid, powder and other organic matter samples of physical, mechanical and chemical properties .Now, it is widely attention and application [1~3].
In some cases, it is very serious, which affects the prediction correction of model establishment and composition or nature of unknown samples.
In the situation that the absorbance and the concentration of samples have good linear relationship and the chemical properties are similar, MSC shows good correction effect.
The NIR spectrum is affected by many factors, such as: effects of collinearity, physical properties, scattering.

However, the approaches stated above are unable to take into account and counter the uncertainties arising from the natural of geometry, material properties and loading.
In reality, the information on load and structural properties are lacking and sometimes it is difficult to be obtained [6].
The requirement for the accuracy and efficiency approach for assessing uncertainty in loading, geometry, material properties, manufacturing processes and operating environment have increased significantly.
In addition, the factor that affects the developed simulation of FFEM is the number of fuzzy parameters.
[7] Langley, R.S., Journal of Engineering Mechanical.