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Mechanical expanding is an important process to ensure the quality of the longitudinally Submerged Arc Welding (LSAW) pipe’s production [4-5], mechanical expanding may eliminate the residual stress caused by forming and welding, improve the internal stress distribution of steel, but also have a negative impact, such as reduce the thickness of the tube wall, generate cracks nearby the heat affected zone and so on, when the improper parameters are used.
Finite element Model for Mechanical Expanding Mechanical expanding is a complex process based on plastic deformation theory, some simplification and hypothesis considered when the model is established are as follow [7]: 1) The friction is coulomb friction, and the friction coefficient is a fixed value between the whole expanding; 2) Impact of the thermal effect and temperature factor for the property of the welded pipe are not considered.
The mechanical expanding model based on ABAQUS is shown in Fig. 1.
Fig.1 Finite element model of mechanical expanding The material properties of sheet have fluctuation in the influence of pipeline steel rolling, shown in Table. 1 Tabl. 1 Material property parameters of Q235A properties C Mn Si P S contents 0.12～0.20 0.30～0.7 <0.30 <0.045 <0.045 The range of elastic modulus E of Q235A grade pipeline steel generally is 200 Gpa-210 Gpa, and the range of yield strength σs is 363 Mpa-490 Mpa.
Simulation Results Fig. 2 is the deformation state of the mechanical expanding for the welded pipe. 

Steel fiber concrete multi-ribbed composite slab system includes material composite and structure type composite, which has good mechanical and thermal insulation properties.
The influence of the factors can be analyzed by the finite element analysis method.
The method also can make optimization for various factors, so it is an effective complement for structural tests.
In this paper, basing on the effect of steel fiber on the mechanical properties of the structure, some key issues, such as material model, finite element model and the simulation method of steel fiber, were discussed.
For the structure in torsion or composite torsion, the longitudinal reinforcement and stirrups are all affecting the bearing capacity of the component, so steel fibers should be equivalent in two directions.

In high speed ball-end milling hardened steel, the increase of hardened steel hardness and cutting efficiency make cutting loads changing, and fuzzy and uncertain properties exist in evaluating cutting vibration and machining surface quality.
Grey incidence matrix of high speed ball-end milling characteristic reveals the interaction level of characteristic and influencing factors.
At present, there are few researches on influence of parameters interaction on the process of high speed milling, fuzzy and uncertain properties exist in evaluating the performance of high speed ball-end milling hardened steel [8], it is necessary to probe into the characteristic and influencing factors.
The results show that there are the different levels of interaction among the characteristic and influencing factors in high speed ball-end milling hardened steel, and fuzzy and uncertain properties exist in evaluating the interactions because the information of behavior and control parameter is imperfection.
Row spacing and inclination angle are important factors affecting the characteristic of high speed ball-end milling hardened steel.

Growing industrial sector is putting focus the composite materials which give better mechanical properties than the materials being used for many years.
Tamer Ozben investigated the mechanical properties and the effects of machining parameters on tool wear and surface roughness of silicon carbide particulate (SiC) reinforced aluminum MMC for different volume fraction.
It was observed that the increase in reinforcement addition produced better mechanical properties such as impact toughness and hardness.
From the analysis, it can be concluded that depth of cut (rank 1) followed by cutting speed (rank 2) and feed rate (rank 3), are significantly affecting MRR.
Investigation of mechanical and machinability properties of SiC particle reinforced Al-MMC.

There are a wide range of ceramic coatings that can be applied to metal components in order to enhance their functional properties.
Hardness and porosity are the two main factors that are properties of the above requirements.
Previous literatures show that there are a lot of factors affecting the desired characteristics.
The levels of factors are selected as three based on Taguchi design.
Pang, Structure characterization and mechanical properties of crystalline alumina coatings on stainless steel fabricated via sol-gel technology and fibre laser processing, J.

Introduction Ti-15V-3Cr-3Sn-3Al (Ti-15-3) titanium alloy is a kind of metastable β-titanium alloy, known as low-cost, high-intensity, and good properties in cold rolling and cold forming process.
This would definitely cause spring back phenomenon [5-8], which has severely influences on forming precision, while researches related to the mechanism and controlling factors of spring back are still inadequate.
V-shaped bending spring-back influencing factors and experimental Study, Forging & Stamping Technology. 5(2002) 22-25
Influencing factors and contrl methods for bending spring-back workpeice, Aerospace Manufacturing Technology. 2(2007) 57-59
Zhan, et al., Coupling effects of material properties and the bending angle on the springback angle of a titanium alloy tube during numerically controlled bending, Materials and Design. 31(2010) 2001–2010

Several design recommendations and construction measures about reinforcements and some sensitive factors mentioned above are proposed to control cracks.
Causes analysis of cracks Box girder cracks are caused by many factors[1] which involve prestressed elements such as longitudinal strand, transverse strand, vertical tendon, box girder factors such as shear lag, warping, distortion, torsion, load factors such as shrinkage and creep of concrete, bearing settlement, temperature gradient, dynamic load, configuration factors such as box girder height, span arrangement, web thickness, diaphragm set and the others, some cracks are the result of several factors.
The following two bridges with typical cracks are analyzed by finite element method to explore the crack causes and the relevant influence factors of large span prestressed concrete continuous box girder bridges.
Increasing a closed steel frame in the box room every 3 meters can improve the mechanical properties of the whole box girder(Fig.3).
The bottom plate mechanical properties are improved due to the increased vertical tension rod and anchorage beams.

Whisker-toughening ceramic cutting tools synthesized by carbothermal reduction method can also greatly improve its comprehensive mechanical properties and cutting performance.
The mechanical properties of the ceramic tools in this experiment are shown in Table 1.
Table1 The mechanical properties of the ceramic tools Ceramic tools Flexural strength [MPa] Fracture toughness [MPa•m1/2] Hardness [HV/Gpa] LTW310 752.5 8.83 21.9 LTW510 812.9 7.64 20.0 LTW710 753.8 8.12 20.2 Results and Discussion Wear Performance.
It is verified by mechanical properties of the ceramic tools in this experiment.
One of the influencing factors for flank wear is the molar ratio of C/Ti in the whisker fabricated by carbothermal reduction process.

However, the effect of the cold strain on the static mechanical properties and creep resistance of Al-Cu-Mg-Ag alloys has not been sufficiently investigated.
Intermediate deformation deteriorates the creep properties.
It is worth noting that elongation-to-failure under creep conditions is lower by factors of about 2 or 3 in comparison with tensile test.
It seems that the YS and UTS at room temperature and rupture time or minimal creep rate at 150°C are the key mechanical properties of this material but these properties are typically opposite to each other.
Zeng, Enhanced mechanical properties in an Al-Cu-Mg-Ag alloy by duplex aging, Mater.

Yang et al. [12] studied the microstructure and mechanical properties of a Ni-based superalloy with refined grains.
In this paper, the mechanism that Microcast-X fine grain casting affects microcrystalline microstructure and mechanical properties of K492M alloy was studied compared with conventional casting.
Discussion Compared with single crystal superalloy, the factors affect mechanical property of material are more complex, including grain size, dendrite arm spacing and secondary strengthening phase such as γ′ phase and carbide.
Gai, Investigation on mechanical properties of fine grain cast by mould agitation, J.
Hu, Microstructure and mechanical properties of a ni-based superalloy with refined grains, Acta.