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Under the influence of external environmental factors (load, temperature, etc.), the state of material would vary.
The ability of a structure to resist the influence of external factors is one of the basic properties of materials. 1.1 Basic assumptions The presence of full state function is based on the following assumptions: (1) The material is composed of a large amount of basic elements which form a structure; (2) The structure of the materials can be destroyed.
When the strength of the material does not vary with the external factors, the diameter of tubular surface would no longer vary.
The actual material properties are very complex.
Therefore, these variables are actually the influential factors for directions.

In detail, a spiral tool path is given to the tool, after the sinking phase with the aim to enhance the final joint mechanical properties [12].
This model is used to investigate the distribution of temperature, strain and strain rate in the heat affected zone and the weld nugget during the sinking stage.
Then a heat affected zone (HAZ, C) is reached, in which material has undergone a thermal cycle which has modified the microstructure and the mechanical properties.
A constant shear friction factor of 0.46 was used for the tool-sheet interface on the basis of a previous experimental thermal characterization and of a numerical sensitivity analysis for the shear friction factor m performed for butt joints [14].
The grain dimension is in direct proportion to the inverse of the Zener-Holomon parameter, which in turn, as known, depends from the temperature, the strain rate and the CDRX activation energy constant Q [13]: )exp(RT Q Z • = ε (2) The present model, through a proper subroutine, is able to predict the Z parameter distribution, giving important information about the final microstructure of the joint and thus its mechanical properties.

Research on the Modeling of Metal Material Properties Based on Logistic Model Zhang Shiyu a, Li Xilingb Beijing Union University, Beisihuan East Road 97#, Chaoyang district, Beijing, China 100101 a gltshiyu@buu.edu.cn, b gltxiling@buu.edu.cn Keywords: logistic model, mathematical modeling, metal material properties, hardenability Abstract.
While we can not explain the principle of the mechanism of the various factors, but a large number of experimental data has good stability, indicating that this statistical model to reflect the characteristics and laws of a certain nature of things.
In this paper, authors attempt to apply logistic model in the research area of metal material properties.
It can be seen in Table 3, which the coefficient of determination R2 is 0.98, identifying that affecting factors interpret the total variation scope .
[8] Mechanical Engineering Manual ( Volume 3 ) , submitted to Mechanical Industry Press, Beijing 1982.9 [9] Socio-economic statistical principles, China Statistics Press, Beijing ,1980,p490

Strength and Fatigue Properties of Used Materials.
The second relevant area for fatigue life prediction is a determination of necessary (namely mechanical) properties of used constructional materials in analysed points of system.
Key factors affecting the intensity of fatigue damage cumulation Four principal factors influencing the structure design procedure are as follows: · working loads, · material and its properties, · production and form of the component (detail), · technology and operation .
Properties of Structure Material.
The operating conditions and outside surroundings factors aggressiveness are also tightly connected with the changes of surface layer properties during technical life of a part or detail.

Measured defects affect the steel scaffolding structure, leading to serious security risks.
to become the main effect of initial imperfection factors.
Calculations can be found in the rod geometry, material properties of the structure will have an impact, relative to the ideal structure, the ultimate bearing capacity have reduced about 10%.Therefore, the tube material itself defect structure is influential, material defects in the structure analysis to be appropriate to consider.
The article systematically studied nonlinear mechanical properties of steel tubular scaffold with initial imperfections and defects on the ultimate bearing capacity of research, based on nonlinear finite element theory, the theoretical analysis and numerical calculation, It has some theoretical and practical significance, the main conclusions are as follows: 1)The use of stochastic finite element method, the ultimate bearing capacity of the different conditions of tightening torque calculation and found that the geometry of the rod, and material properties on the structure will have an impact，Relative to the ideal structure, the ultimate bearing capacity lower than the obvious, reducing about 10%. . 2)Analysis of the defects of the fastener scaffold structure, consistent contrast defect method and the random-defect method two analysis methods, to draw a consistent defect method to defects in the value of taking 3L/1000 unsafe.
It described the pole bending defects affect the structural capacity of the main defects.

The Synthesis and Feature rearch on the Thermosensitive Hydrogels(NIPA-co-AAm) Zhu Xiufang1, a, Yang Ming1, b, Zhang Hongxia1, c, Nie Yujing1, d 1Department of material engineering, Hubei University of automotive technology, China ashine_1113@163.com byang_min6@126.com cufoxhz@126.com dnieyujing@sina.com Keywords: Salinity, hydrogels, mechanical properties Abstract.
Tensile tests were conducted on a N-isopropylacrylamide(NIPA)-acrylamide(AAm) comonomer gel sensitive to variations in environmental temperature. and salinity Mechanical properties (Young’s modulus) were determined at different levels of swelling equilibrium.
Shifts in the mechanical properties were observed between samples tested in the swollen and unswollen states.
The mechanical tensile testing machine equipped with a 18 N load cell, was used for measuring the mechanical properties of the hydrogel.
As shown in the Fig. 6, putting the dry hydrogel disc in the ionic strength solution, we can see that 100min later, the hydrogel reach their equilibrium, and the ionic strength value is the key factor which affect the hydrogel swelling ratio, swelling ratio of hydrogel immersed in the 0M ionic strength is the highest, and the one immersed in the 0.2M ionic strength is larger than in the 1.0M ionic strength.

Focusing on the practice pavement sections using LSAM as base in Hangzhou municipal roads, the effect factors of subgrade modulus, base modulus and base thickness on surface deflection and bending strain in base bottom is analyzed.
Based on the test of the large-stone asphalt macadam base on a road in Hangzhou, it is analyzed that how the subgrade modulus, base modulus, base thickness and thickness of the surface layer affect the mechanical properties of asphalt pavement structure by the software of BISAR3.0.
Table 5-Pavement structure and parameters Layer Location Material Thickness(cm) Modulus(MPa) Passion ratio Surface Upper surface AC-13 4 — 0.25 Middle surface AC-20 5 — 0.25 Bottom surface AC-25 7 — 0.25 Base LSAM 20~40:5 — 0.3 Sub-base Graded broken stone/ Slag 30 30~480:50 0.3 Subgrade — — 10~30:5 0.35 Main Factors Affecting Mechanical Behavior of LSAM Asphalt Pavement 2.1 Analysis of subgrade modulus In the analysis, the structure of pavement consists of 4+5+7cm surface layers, 30cm LSAM asphalt base and 30cm sub-base; while the other parameters remain unchanged, sub-base modulus ranges from 30Mpa to 480Mpa; under each selected sub-base modulus, the subgrade modulus increases from 10MPa to 30MPa.
It figures out how the base thickness affects the structural mechanics indexes of flexible base pavement, and the results are shown in Figure 5 and Figure 6.
Analysis of Influence of Base Structural Parameters on Mechanical Response of Asphalt Concrete Pavement[J].

However, most starch-based plastics exhibit poor mechanical properties.
In order to develop composites with better mechanical properties and environmental performance, it is necessary to increase the hydrophobicity of the plant fiber to improve the interface between the matrix and the fibers.
Analysis of variance was employed using Design Expert 7.0 and significant factors affecting the tensile strength were determined at 95% confidence level.
Table 2.Thermoplastic Starch Matrix, Untreated and Treated Abaca Fiber Properties.
Mechanical Properties of Abaca Fiber Reinforced Urea Formaldehyde Composites.

As a result, to obtain the exact temperature history, it is necessary to examine thermal properties of the concrete.
Meanwhile, because several well-known factors, such as roughness of concrete surface, materials of form, and flow characteristics influence on the heat transfer coefficient, it is not easy to simply define the coefficient.
Branco et al. [4] and Mendes [5] recommended that influencing factors, which affects the coefficient, should be verified using experimental results and proposed a prediction model as a function of concrete surface’s roughness and wind velocity.
Table 1 shows physical properties of used materials.
In this study, two different mixture proportions were used to investigate if the heat transfer coefficient was independent of concrete properties.

Introduction The pure machined titanium implants are widely used in orthopedic and dental surgeries due to their excellent biocompatibility and mechanical properties which lead to successful clinical performance in implant dentistry.
Recently, published in vivo investigations have shown significantly improved bone tissue reactions by modification of the surface oxide properties of titanium[7].
These results will affect the initial stability and removal torques and histological osseous healing of the implant[3,5].
The insulin-like growth factor 1 receptor binds insulin-like growth factor with a high affinity.
Among the molecules affecting the cell mitogenecity, fibroblast growth factor-7, 5, Platelet derived growth factor C peptide, Bone morphogenic protein 1, Transforming growth factor β1 were definitely down regulated on anodized surface compared with machined surface.