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The stress concentration factor is calculated for a ply with modeling crack under the condition of different loads.
This material is utilized by the aviation, high speed railway industry due to its relative lightweight and high strength, as well as its excellent gap sensitivity and stress anti-rust property.
The stress distribution around crack and rivet joints were studied for high strength aluminum alloys by Lock-in thermography, and the stress concentration factors of crack structure component were calculated under the condition of different loads.
Fig.1 shows the structure and the finite element mesh of the high strength aluminum alloy ANSI 7071. the ANSI 7071 mechanical and thermal properties have been given, the Young's modulus E is 69GPa, the Poisson's ration v is 0.33, the special heat c is 890 J/(Kg℃), the thermal diffusion coefficient α is 23.5 m 2/s, and the density ρ is 27100 Kg/m 3 The amplitude of sinusoidal load is 5400N and the load modulation frequency is 1Hz.
Ft=4.4KN X Y a) Experimental results Ft=4.4KN X Y b) FEM results c) Comparison along X d) Comparison along Y Fig.6 Stress distribution of crack structure Ft=5.4KN Ft=8.4KN Ft=11.4KN Ft=15.4KN Ft=17.4KN e) Stress distribution of different loads It can be known that the stress concentration factor is not affected by load for given crack geometry shape under different loads, for this crack structure component of ANSI 7071 high strength aluminum alloy, the stress concentration factor Kt is about 2.0 from Fig.7.

Currently, there are a few scholars who have researched the mechanism about production of the shrinkage cavities at boss extrusion process of sheet metal and some factors which can affect the shrinkage cavities.
However, there is no further overall research on the impact factors to the shrinkage cavities.
The metal materials of this region can flow to center axis of symmetry, however, with the increase of deformation degree, the surplus materials will be less and less between the punch-dies and flow properties of materials is gradually weakened to makes materials at surrounding of the die flow to the center difficultiy.
In order to eliminate influence of some factors and to make simulation results comparable, it keep the relative extrusion capacity same, which means that keep the ratio of blank thickness and primitive blank thickness same and the ratio is 50% in following.
Pc stands for the value of pressure that counter force affected on the sheet.

The material properties used in the analyses are shown in Table 2 [14].
Detailed material properties used for these welds can be seen in Ref. [14].
This clearly illustrates the main features of life reduction due to the presence of welds, an additional life reduction due to increased axial stress and the more limited life reduction due to geometry factors.
Some typical numerical results obtained for a number of pressurised pipe and weld related components, are presented to illustrate the main behaviour, from which the effects of some factors (e.g. geometry, material and loading modes), which affect the failure behaviour of high temperature components under creep, can be seen.
FE analyses have been primarily concerned with the estimation of failure life and to assess factors influencing the life of high temperature components.

Although domestic scholars have done some researches on factors contributing to the impact on mechanical behavior of joints and have collected the calculating ways of the thickness of the beam overhanging terminal plates [4~6], their researches are still in the starting stage.
The factors that influence the seismic behavior are also mentioned in the article.
Selection of the Nodes Changing Parameters Because the complex stress of the semi-rigid joints, it is affected by many parameters.
Many series of specimen are designed and derived from BS specimen to study the each parameter’s influence on its mechanical performances.
The Property of Semirigid Beam-to-column Connection of Multistory and Highrise Steel Frame Structure.

There were three main factors of the weld fusion line: 1) The base metal was quenched by the heat effect of the bead weld, which led to the increase of hardness; 2) Stress causes the change of hardness.
The above statement showed that the pressure pipe cracking was high temperature fatigue crack, and the material segregation and mechanical properties are not qualified, which led to the decrease of the fatigue strength of the material
The material segregation and mechanical properties lead to the decrease of the fatigue strength
Microstructure and properties of T91 steel weld joint welded by nickel-based EPRI P87 welding material [J], Heat Treat of Metals, 40-11 (2015) 44-47
Studies on high-temperature microstructures and mechanical properties of the T92/HR3C and T92/TP347H dissimilar steel weld joints [D], Hefei: Hefei Polytechnic University, 2012

Incoloy 800HT is an iron-nickel-chromium-based superalloy known for its ability to retain mechanical properties at high temperatures and its exceptional resistance to oxidation, carburization, and corrosion.
Optimization of WEDM parameters was performed by Manikandan et al. [6] for Incoloy 800 using the Taguchi-Grey approach to find peak current followed by pulse on time as the most influential factors on MRR, surface roughness and overcut.
Chemical composition and physical properties of Incoloy 800HT.
Some of the important chemical compositions and physical properties of Incoloy 800HT is given in Table 1.
Among these, peak current was identified as the most critical factor in enhancing MRR; however, it adversely affected surface finish due to increased thermal energy and larger crater formation.

It was regarded as one of the most desirable materials to prepare short wavelength optoelectronic devices for the good optoelectronic properties and excellent mechanical behavior.
The type and quality of substrate material are key factors that affect epitaxial growth, so hexagonal phase sapphire has been chosen for substrate in this paper.

Their appeal is attributed to their potential to display unusual physical and mechanical properties [1,2].
Both electrostatic and electrosteric effects can exist in aqueous suspensions [16] with many factors, such as the competitive affinities of any polyelectrolyte present with the particle surface and the surrounding medium, affecting suspension stability [17].
In the second, the effect of the polyelectrolytes PAA and PMAA on aqueous suspensions of nano Y-PSZ particles has been evaluated via measurement of the electrokinetic properties of the particle surface, the hydrodynamic properties of the dispersed particles and the rheological properties of the ceramic slips.
The resultant properties are shown in table 1 below.
Key properties of the yttria-doped zirconias.

However there are several uncontrolled factors that may affect the degree scores for spasticity level either from the patients or the therapists themselves, such as the activity engaged by the patients before the tests and the testing position.
Modified Ashworth Scale (taken from Bohannon and Smith, 1987) 0 No increase in muscle tone 1 Slight increase in muscle tone, manifested by a catch and release or by minimal 1+ Slight increase in muscle tone, manifested by a catch, followed by minimal resistance throughout the remainder (less than half) of the ROM 2 More marked increase in muscle tone through most of the ROM but affected part(s) easily moved 3 Considerable increase in muscle tone, passive movement difficult 4 Affected part(s) rigid in flexion or extension Fig. 2.
The results were also affected by the therapists’s seating positions during session trials which had them produce different forces.
The position of the therapists affects the detected force at the strain gauge that produces shear strain.
"A Review of the properties and limitations of the Ashworth Scales as measures of Spasticity" Clin Rehabil 1999. 13:373

The rock burst has already became the important factors threatening work safety for personnel and equipment, seriously hinder the smooth progress of the project, must take into account.
Can not reflect the mechanical and dynamic characteristics of rock burst; because of the mine structure post peak stiffness is difficult to determine the application receives many limits. energy theory Explain the dynamics characteristics of rock burst[7]. didn’t specify the equilibrium properties and failure conditions[4].
Workload big, affects the construction schedule[13]; The application is narrow. acoustic emission and microseismic To achieve long-term,continuous and dynamicmonitoring[12].
Easily affected by external environment; Accuracy needs to be improved; The warning time is short[14]; Affect the construction schedule. microgravity Simple operation, low cost, little interference, high precision[14].
Easily affected by external environment.