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Introduction Tube hydroforming process has the advantages of reduced weight, saved material, reduced energy consumption, simplified production processing, reduced production costs, high surface quality, good mechanical properties when compared with traditional stamping and welding craft works.
The main factors that affect the hydroforming process are the material formability, part structure and shape, internal pressure loading path, axial feed rate and feed speed, lubrication conditions between tube and die.
As can be seen from the figure, there are some unfavorable factors while using a hydroforming process machining: the maximum value is close to 178mm while the minimum cross-sectional perimeter is only 132mm with margin close to 35%; the left cross-sectional is relatively flat, so there is deep drawing during forming process; axial-direction feed amount is large.
Cross-sectional perimeter/mm Longitudinal axis/mm Fig.1 Properties and Perimeters of cross-sections 1.2 Numerical analysis Model The initial outer diameter of tube is 42.2mm，and the initial wall thickness is2.0mm.
STKM-11A is selected as the tube material, thanks to its equivalent and satisfied stress and strain properties. 1.3 Stimulation experiment theme After part structure and shape, materials, lubrication conditions and other factors are determined, it is necessary to provide a reasonable match relationship between the internal pressure loading and axial feed to ensure that the tubes can be successfully molded.

There is therefore a need for models that predict the electroelastic properties and describe the deformation process of such piezoelectric materials.
Microscopic damages unlike submicroscopic damages, which under unloading, as a rule, vanish (are healed), are of irreversible character (i.e. they remain in the form of microcracks) and at a macrolevel are manifested as changes in mechanical properties of a material, in particular, in its deformability.
At the second phase, the method for determining effective electroelastic properties of the damaged medium and the model of accumulation of microdamages are employed.
To approximate distributions of the microstrength properties of structural elements the power law is used
Dependence of the stress from mechanical strain Because of the direct and inverse piezoelectric effect, we can see that the presence of an electric field affects the stress-strain dependence.

In the result of the evaluation of mechanical properties of these steels, it was confirmed there were steels which indicated different elongation even if they had almost same volume fraction and carbon content of retained austenite.
But recently there are some results which can to be interpreted by these factors.
Tensile properties (tensile strength (TS), total elongation (EL), uniform elongation (uEL)) were evaluated using JIS No.5 specimens.
Result Fig. 1 indicates the tensile properties of the heat treated specimens.
By the way, it is well known that there are a lot of factors which affect diffraction profiles, for example, dislocation density, arrangement of dislocation, applied strain, texture and so on.

Introduction Cold formed and precipitation hardened aluminium alloys are of great interest in the automotive and in the aircraft industry due to their favourable mechanical properties in combination with a low specific weight.
The local heating results in inhomogeneous recrystallisation processes and at least in a strong loss of the initial mechanical properties.
As different welding processes like metal arc welding, tungsten inert gas welding or beam welding processes generate rather different softening zones, these zones may act like structural notches due to the locally varying material properties.
The term metallurgical notch refers to the abrupt changing of mechanical properties in the environment of the weld seam as a result of the applied heat treatment. [1] In use, this distribution of mechanical properties can create complex strain and stress conditions.
While the welded naturally hard samples behave like the base material, welded samples made of the alloys EN AW 6082 could not reach the mechanical properties of the base material.

Analysis of the Influence of Static Flow Resistance on the Sound Absorption Properties of Aluminum Foam BAO Huaiqian1, a, ZHANG Ning1, b and HOU Xuegang2, c 1College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao, Shandong, China, 266590 2Rizhao Polytechnic, Rizhao, Shandong, China, 276826 abhqian@163.com, bzhangn188@163.com, cjdhxg@126.com Keywords: Aluminum Foam; Sound absorption; Flow resistance; Backing.
The paper also calculates and analyzes the influence of Static flow resistance on the sound absorption properties in the rigidity and cavity backing.
The paper analyzed the influence of the thickness of the backing of aluminum foam and static flow resistance on the sound absorption properties.
Moreover, we can achieve the best sound absorption properties by controlling the flow resistance.
The backing can improve the integral sound absorption properties and make the peak frequency moves to the range of middle and low.

The cryo-insulation performance of vehicular tank directly affects the security of LNG transport greatly.
Therefore, the cryo-insulation performance of vehicular tank directly affects the security of LNG transport greatly.
Compared with low temperature adaptation range, low temperature deformation rate, tensile strength, and other key mechanical properties, 9Ni steel is better than other steels in application of LNG tank at -163℃.
temperature (℃) 200 280~460 140 140 160 240~260 854 1600 Compared with the thermal insulation material, rigid polyurethane foam has better insulation properties than other materials.
Thermal analysis above is based on the heat leakage under steady state heat transfer condition, while ignore heat transfer between gas and LNG in the tank, heat convection between gas and tank shell, volatility of environmental temperature and light factors, inhomogeneity of material, pressure of LNG tank, and composition of LNG.

Effect of CO2 on Anti-corrosion Property of a Polyurea Coating Modified with Organosilicone Qinghao Shi1, a, Bingying Wang1, b*and Bin Zhao1, c 1 College of Mechanical and Electrical Engineering, China University of Petroleum, Qingdao 266580，China asqhao1990@126.com, btdwby2004@126.com, cupc0672@163.com Keywords: High temperature high pressure, Polyurea, CO2 partial pressure, Corrosion, EIS.
Introduction CO2 partial pressure is one of the important influence factors on CO2 corrosion, the PH value of solution or the concentration of a series of chemical compound of CO2 dissolved in the solution will exert an influence directly and further affect the rate of corrosion [1-2].
Due to excellent corrosion resistance, good mechanical properties and free of contamination, polyurea coatings are widely used in industrial antisepsis and mechanical wear protection lining areas [3-5].
The first time constant is the constant of coating properties, and the second time constant is a time constant of the electrical double layer.
This indicates that after the high-pressure high-temperature corrosion, the protective properties of the coating greatly reduced, generates serious corrosion, and the occurrence of dual capacitive impedance arc indicates that the corrosion resistance effect of the polyurea coating is basically lose, the corrosion resistance process transfers from the control process of the coating gaps through the corrosion medium into the charge transit process control of corrosion of the metal substrate.

The found from the actual investigation are that curing time and curing conditions are not uniform is the main factors that restrict the assembled composite wallboard production efficiency and increase the cost.
For example, although extend the rest period could enhance the strength of concrete, durability and volume stability, but too long rest period could affect the production efficiency, so strength, durability, volume stability, and the demand of production cycle must be considered when selecting parameters[1~5].
By the contrast analysis of “Code for production construction and quality acceptance of concrete member in assembly integrated precast building” in Shanghai, “The design and construction technical guide for framed concrete structure”provided by Kajima Corporation in Japan, “Production and acceptance procedures of precast concrete component” in Liaoning province, and consider the problems in the actual production process, this paper has given the steam-system, which the rest period should be less than 2 hours, 3 hours is suggested to ensure the performance of the component development without affecting the production efficiency(the rest period is determined by environment temperature, which is concluded by the experimental results of influence of stop time on concrete performance under different environment temperatures),method such as covering membrane, humidification should be taken to keep the components humid, the temperature in plant should not be less than 5℃, heating rate should be
The influence on mechanical properties of reactive powder concrete curing.
(in Chinese) [4] Liu Baoju, Xie Youjun, Zhou Shiqiong, etal．Some factors affecting early compressive strength of steam-curing concrete with ultrafine fly ash.

It is demonstrated that the weld penetration shape factor depends on the laser beam fluence and the pulse duration.
In its turn, the weld penetration shape factor effects the quality of obtained irradiation zones.
The concentrated energy flows are widely used in processing surfaces of various materials to improve hardening, wear resistance, mechanical and fatigue strengths in their surface layers.
Owing to residual austenite to martensite reversion during the pulsed laser irradiation, these steels can be used as hardening wear-resistant coating on friction couples [11-12].To our knowledge, current research is focused on influence of energy parameters of electron beam or plasma arc on the structure formation and properties of such coatings.
Degterev, Structure and properties plasma-powder coating, Bulletin of the Tomsk Polytechnic University.

Introduction The epoxy resin has excellent mechanical properties, electrical properties, adhesion properties, heat resistance, solvent resistance and it is easy to mold[1].
Silicone-modified epoxy resin can improve the toughness, high temperature resistance and boiling resistance and other properties of the epoxy resin [3,4] .
The paper mainly study on factors of the synthesis reaction, and prepare silicone-modified epoxy resin, which has good hue and balanced epoxy value, molecular weight as well as molecular weight distribution[7].
GPC test of the synthesis product The molecular weight of the polymer is an important factor to affect the performance of polymer materials.
Characterization and properties of new silicone-containing epoxy resin[J].