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Lamikiz1,d 1Department of Mechanical Engineering – University of the Basque Country UPV/EHU.
The conventional thermal models are focused on solving the differential equation of temperature field, considering the laser as heat source and thermal properties of each material.
In this case data will be taken out about unknown material properties to characterized total power losses in the process.
On the other hand the heat exchange by radiation is considered as component of the losses factor inside the nodes of the part radiated by the laser.
It is considered a nonlinear model with temperature dependant material properties, such as conductivity.

An important additional requirement is that the partial safety factors recommended in EN 1999 shall in ultimate limit state (ULS) be multiplied by 1,1 and in accidental limit state (ALS) with 0,9.
The mechanical properties in haz for thicknesses above 15 mm have an additional reduction according to the standard.
Reduction factors for haz for welding of EN AW 5083 H321 and EN AW 6082 T6 depending of the material thicknesses.
The same reduction factors and width of haz as given for the actual alloys in EN 1999-1-1 is used for design of FSW joints.
Structural aluminium fabrication, Edition 2, 2015 [5] EN 1090-3 Execution of steel structures and aluminium structures – Part 3: Technical requirements for aluminium structures [6] Marine Aluminium: Load test HD top plank, L = 4300 mm – Test report and results, Report no.: 1630000-MA-7010-N-RA-002-0001 [7] EN 1999-1-3 Eurocode 9: Design of aluminium structures – Part 1-3: Structures susceptible to fatigue [8] Steinar Lundberg, Nils Jakob Tjøstheim: Mechanical properties in Heat Affected Zone of welded EN AW 6082 T6 (Hydro Aluminium Report) [9] Steinar Lundberg, Nils Jakob Tjøstheim: Mechanical properties in Heat Affected Zone of welded EN AW 5083 H321 (Hydro Aluminium Report) [10] Steinar Lundberg, Randi Mørkrid: Mechanical properties in Heat Affected Zone of welded EN AW 6060 T66 and EN AW 6063 T66 (preliminary report)

Without affecting the overall stiffness, small parts and very thin parts in assembly are removed which include screws, nuts, pins and gaskets, etc.
Material Property Setting.
Material property setting is shown in table 1.
It is an important analysis method for studying the dynamic properties of the structure.
Comprehensively considering all various factors, the improving measures are put forward for: (1) Improvement of the bed structure.

Special attention is devoted to mechanical properties of hard nanocomposite coatings and open problems in their formation and characterization.
Mechanical properties of hard nanocomposite coatings Mechanical properties of nanocomposite coatings are well characterized by their hardness, H, the Young´s modulus E* =E/(1-�2) and elastic recovery We.
Mechanical properties of nanocomposite coatings strongly depend on (i) elements which forms individual phases and (ii) relative content of individual phases in the nanocomposite, see Fig.1.
This is due to the fact that films are formed in a medium which is generated in consequence of action of many factors (process parameters) which are mutually very tigthly coupled.
Macrostress, grain size, film structure, binding energy, grain boundary interaction, other factors or their combinations?

Water Content Test As a solvent and media,water is the raw material of crop photosynthesis,and also an important factor for keeping metabolism and constituting the plant’s body.When water is shortage,the crops will reduce productions,even die[2].The water mainly coming from the moisture of soil is absorbed by crops’ roots,so the water content in the soil can directly affect the growth and yield of crops[3].Our team tested the water content in the fresh samples by the way called drying and weighing.The results are shown by Form 3-1.
WC(%) A1 14.59 C1 11.82 A2 22.81 C2 21.41 A3 46.40 C3 43.49 B1 11.34 D1 13.41 B2 22.21 D2 22.81 B3 42.51 D3 47.68 PH Value Wheat is the main crops in China.Its yield and quality is affected by their own characteristics,but the main factor is the environment of growth,including soil conditions,climate factors, geographic location,etc.The PH value can largely affect the fertility factors , physical and chemical properties in soil[4].The best PH value for wheat growing is 6.5.When the PH value is higher than 7 or lower than 6,the activity of amylase, protease and lipase are reduced during the wheat seeding;the rate of breathing and endosperm decomposing become slowly;germination is slow;the seeding grow slowly caused by low activity of roots and nitrate reductase,chlorophyll content,rate of photosynthesis
The form 3-3 shows that the water suction in Class A is a little higher than Class C,but it is lower than Class B and D.However, the thickness of covered soil in Class C is approximately two times of Class A which cause the cost of reclamation much more higher,and the water content in Class C is lower than Class A on the natural condition.So according to all the above factors,Class A is the best
Conclusion The on-site investigations and researches of reclaimed land in Shangyao town show that:①The layer of fly ash has good properties of water-resisting, water-saving, water-holding and water-supplying for covered soil;②There are different properties of water-saving,water-holding and water-supplying between different levels of covered soil.Under the lowest condition of soil the wheat needs, considering the costs of reclamation and efficiencies of yield at the same time,the best thickness of covered soil in reclaimed land of Shangyao is between 24cm and 40cm.
[6] Fink P K.Lusth J C.Expert system and diagnostic expertise in the mechanical and electrical domains[J].IEEE Trans SMC,1987,17(3):340-349

Due to the shrinkage, creep, friction and other factors, the pre-stress applied to the beam is not a constant.
Introduction Being good mechanical properties, the pre-stressed concrete box girder is widely used on highway and city bridges.
Therefore, scholars in China and other countries have made a thorough study of the problem and found that the pre-stress loss is one of the main factors affecting the stiffness of the pre-stressed concrete bridge in service.
In order to simplify the problem, the pre-stress loss of the beam at different location is regarded as a constant which comprehensively reflects the influence of the internal and external factors.
Due to the measured deflection of bridge under different time, temperature and other factors, the value is looked upon as a comprehensive value that is correspond with the particular period of time and particular condition.

In abrasive belt grinding Titanium alloy blade of aviation engine experiment, through the single factor experiment method, the influence of abrasive belt linear speed and work-piece feeding speed on the grinding quantity is discussed.
Blade material requires sufficient mechanical properties, high chemical stability, high resistance to mechanical abrasion performance, good manufacturability, low coefficient of thermal expansion and good damping characteristics [1].
By the method of single factor experiments, paper studies that the influence of abrasive belt linear speed and work-piece feeding speed on the grinding quantity and clogging degree of belt are also analyzed.
If v too high, it will lead to grain enough to cut the surface of work-piece, producing only sliding and plow, material grinding quantity decreased, affecting the material removal rate continues to rise.
When grinding time is 3 ~ 30 min or so, the clogging degree of belt does not change significantly, so the grinding process is relatively stable. 3） In the influence clogging degree of abrasive belt factors, the work-piece feeding speed exceed abrasive belt linear speed.

Tables 1 presents their chemical composition and mechanical properties used in the experiments, respectively.
The mechanical properties of the material which are shown in Table 1 were used in the calculations, and the materials were assumed to have a linear response.
Table 1 Mechanical properties of the Si3N4 specimen.
We ignored the effect of the residual stresses on the stress intensity factors.
Stress intensity factors at the inside tips of the cracks are plotted in Fig. 5 (b).

Introduction After Iijima discovered carbon nanotubes (CNTs) by arc discharge method [1], many researches are attracted by the good mechanical and electrical properties of CNTs and focused on CNTs-related fields.
Yeh et al. [3] found the effective Young's modulus and effective tensile strength for MWNTs as 953 GPa and 22.3 GPa respectively by deducing experimental mechanical properties of MWNTs/phenolic nanocomposites using modified Halpin-Tsai equation.
Yeh et al. [5] investigated the mechanical properties of the MWNTs/phenolic nanocomposites and observed good adhesion between the MWNTs and the resin from the SEM images of the tensile fracture surface of MWNTs/phenolic nanocomposites.
This is probably due to a better thermal conductivity property of carbon nanotubes.
In this case the nonuniform dispersion of the reinforcement, as shown in Fig. 3, became a dominating factor on the glass transition temperature.

Co-base superalloys have been applied in the stationary compoents of gas turbine owing to their excellent high temperaure properties.
The existing carbides of Ni-base superalloy begin to decompose above 700 o C, and the mechanical properties decrease above 900 o C because of the dissolution or coarsening of γ' phase.
However, the microstructure and mechanical properties are stable above 900 o C in Co-base superalloys.
McLean had reported that the secondary DAS was also affected by solute diffusion, and the cooling rate (GV) was an important factor.
Brooks, Heat Treatment, Structure and Properties of Nonferrous Alloys, US (1982)