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In WE43 the particle distribution affected the onset of dynamic recrystallization.
Introduction In the extruded condition alloys such as AZ31 and ZC71 have been reported to have anisotropic mechanical properties, whilst others such as WE43 and WE54 exhibit isotropic behaviour [1, 2].
These anisotropic mechanical properties in compression and tension appeared to be caused by texture which had evolved during thermomechanical processing [3].
Although deformation mechanisms are reported to affect texture development in magnesium [4], it has also been suggested that differences in texture in magnesium extrusions might be attributed to different recrystallization mechanisms [1].
It is important to develop an understanding of the factors affecting the recrystallization mechanisms in magnesium if the structure-property relationships are to be understood during thermomechanical processing.

Analysis of Stress Distribution of Externally Pre-Stressed Beams under Transverse Loads Peng Zhang1, a, Dan Shen1, b and Shirong Li1, c (1 College of Civil Science and Engineering, Yangzhou University, Yangzhou, China, 225127) auptent@163.com, bshendan123456@126.com, csrli@yzu.edu.cn Key words: Euler-Bernoulli beam theory; External restraint; Parameters analysis Abstract: The size, the position and the arrangement of external restraint will significantly affect the mechanical properties of the structures with the external restraint.
Sun et al.[6] studied the nonlinear mechanical response of concrete beams with post-tensioned external tendons by using both the experimental and finite element method.
The axial force of the external steel bars can be derived as following: , (6) Furthermore, by using the superposition principle, the internal force of the external steel bars under the uniformly distributed load (See in Fig. 3) can be given by Fig 3 Uniformly distributed load arrangement of the simply supported beam (8) In order to facilitate the analysis, we introduce the following dimensionless quantities: , ，，， (9) where reflects the rate of the contribution of the external steel bars on the flexural rigidity of the, is the slenderness ratio, is the eccentricity of the external steel bars, reflects the positional parameters for the external load, integrates the comprehensive reflection of the all the factors on internal forces of the external steel bars.
From Eq.(14) it can be seen that internal force in the external constraint produced by the applied transverse loadings is proportional to factor which depending on the geometry and the physical properties of both the beam and the constraint.

Domestic and foreign scholars have had lots of studies on determination method and influencing factors of surface roughness.
It was an important way for reasonably developing plantation-Mytilaria laosensis to strengthen comprehensive research of the nature and mechanical processing properties , therefore, many experts do a lot on this. [8-9].
To know whether three factors have significant influence on various parameter or not, the variance analysis is carried on.
Research and Evaluation on the Planning and Sanding Properties of Mytilaria laosensis [J].Advanced Materials Research. 2012, 420: 982-986
Study of Physical and Mechanical Properties of Wood from Mytilaria laosensis Plantation [J].Journal of Central South University of Forestry & Technology. 2007,(05): 97-100. ( In Chinese)

However, while using wood in the production of building materials, it is necessary to consider a set of factors, as along with the valuable properties (low average density, ease of handling, etc.) it has a number of negative qualities, which complicate production of construction materials of desirable quality.
Introduction All It's well known that natural wood has a fairly limited lifespan and is exposed to various aggressive environmental factors.
This fact explains the desire to find an alternative to wood of similar properties, but surpassing it in quality.
Researches of Hannah Epmeier, Mats Westin and Andreas Rapp were focused on the sorption and physic mechanical properties of thermally modified wood.
In this regard deep research of physical properties of thermally modified wood filler, as well as the development of new technologies that will significantly improve the physic-mechanical properties of wood-plastic composites is an important task today.

Machining of metals make use of thermal-mechanical FEM model.
Therefore, constitutive model that could true reflect various factors on influence of stress and strain of the processing materials is the basis of ensuring precise results of finite element simulation of cutting process.
Johnson-Cook model is a constitutive Model with good properties, which is used to describe under the condition of the large deformation, high strain rate effect and temperature, especially the model is widely used in the transient and dynamic simulation.
The result is that tool wear and workpiece machining accuracy will be the large affected by cutting heat generated.
Ai: China Mechanical Engineering, VoL.18 (2007) No.6, pp. 746-751.

This is motivated by the fact that fine-grained materials differ significantly from their coarse grained counterparts in physico-chemical, mechanical, etc. properties [4].
In view of the above, the analysis of the effect exerted by structural changes, including GB state, on the mechanical properties (microhardness, ultimate strength and yield strength, deformation to failure, creep parameters) and on the physical properties (electrical resistance) was performed using coarse-grained and nanostructured nickel and copper [6-8].
Thus, the factor determining the unique superplastic properties of 1420-grade alloy in ultrafine-grained state is the formation of strained, non-equilibrium state of grain boundaries after severe plastic deformation.
For what properties is it important?
Kolobov: The increase of DGB influences practically all mechanical properties controlled by diffusion.

The main factor examined in the process of welding duplex steel is the shielding gas and his effect on weld joint properties.
Duplex stainless steels are valued mainly due for their combination of mechanical properties and excellent corrosion resistance.
Welding speed and focus height (distance of laser beam focus from material surface, positive if over the surface) were selected as factors, while the laser power was kept constant at 4 kW.
It can be assumed that these results could lead to desired mechanical properties as well as corrosion resistance.
WESTIN.: Microstructure and properties of welds in the lean duplex stainless steel LDX 2101.

Li [10] proposed that the temporal variable can be explicitly introduced in the mechanical damage evolution law (in terms of damage rate).
Mazzotti [12] proposed to model non-linear creep strain by introducing a stress rate reduction factor as a function of the damage variable in the solidification model [13].
In this model, a scalar mechanical damage variable is associated to the mechanical degradation process of concrete induced by the development of microcracks.
In the case of a severe accident in a nuclear power plant, basic creep will be affected by elevated temperatures and damage.
Vogel, « Concrete: treatment of types and properties in fib Model Code 2010 », Structural Concrete 14 (2013), No. 4 [2] J.M.

Therefore, the mechanical properties behaviour of the alloys is very strongly related to their composition and microstructures.
Introduction Ni-based superalloys are widely used for high-temperature applications due to their excellent mechanical properties for high temperature applications.
Therefore, high-temperature mechanical properties of nickel-base superalloys are further enhanced by moderate additions of tungsten.
The overall alloy composition has a role on the mechanical properties of the materials and microhardness measurement is an important parameter to access their strength.
Conclusions The microstructure, phase stability, and mechanical properties of the alloys 70Ni-15Ti-15W and 90Ni-5Ti-5W were examined.

Under different friction factors, several groups of the rubber O-rings have been analyzed, finding that the friction factor is the reason of un-uniform compression.
If one describes the model with two parameters, the above equation becomes the common Mooney-Rivilin constitutive model: （2） This model can illustrate the mechanical properties of the rubber material very well because it satisfies the accuracy requirements for the practical application of the rubber material deformed less than 150%.
When under different friction factors, the smaller friction factor used, the smaller contact stress and contact area with shorter span L between the maximum and minimum, as shown in fig. 3 to 6.
So the compression rate εm also affects the decreasing slope.
Mechanical science and technology. 2000 (9): 625-626