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The optimisation of sheet metal processes by using numerical simulations has become a key factor to a continuously increasing requirement for time and cost efficiency, for quality improvement and materials saving, in many manufacturing areas such as automotive, aerospace, building, packaging and electronic industries.
The evolution law for the internal variables can be derived from a potential of dissipation which is decomposed into plastic, pψ , and damage, dψ , components as ( )( ) 1 1 1 s p d r Y D s r ψ ψ ψ + −  = + = Φ +   − +   (2) for a process accounting for isotropic hardening and isotropic damage, in which r and s are material and temperature dependent properties and Φ and Y are respectively, the yield function and the damage energy release rate, given by ( ) ( ) ( ) ( ) 2 2 2 2 1 1 : 1 : 2 1 2 1 c c h Y tr tr E D E h D υ σ σ υ σ υ σ σ υ σ + + − − −     = + − − + − −         − − (3) where E and υ denote, respectively, the Young's modulus and the Poisson's ratio of the undamaged material.
A possible alternative to avoid the problem and have a fast integration algorithm that estimates damage evolution with crack closure effects is to decouple the above damage evolution from the plasticity equations, but with the damage variable affecting the plasticity hardening evolution law.
The same numerical model was used to perform another numerical simulation but, in this case, with the integration of the damage model subroutine, thus the computed damage variable affects the plasticity evolution law in the described numerical integration scheme.
Lemaitre: Journal of Engineering Materials and Technology, Transactions of American Society of Mechanical Engineers Vol. 107 (1985), p. 83

At present the domestic and foreign scholars study on the rigid frame structure under static load mechanical properties of a large number of theoretical and experimental research of [2] ～[4], but on a rigid frame structure seismic performance have not been carried out systematic research.
Semi rigid frame structure on the dynamic response, exhibit and rigid frame completely different properties, but also in seismic zone using stiffness great node is not necessarily the most reasonable choice [5].
This article uses the finite element analysis software ANSYS on concrete filled steel tubular frame structure dynamic properties was studied, draw some conclusions for the earthquake zone, put forward suggestions for the design of the frame structure. 2 The establishment of finite element model Concrete filled steel tubular frame structure mainly by beam, column and connected nodes, frame structure is simplified as plane frame.
Using the finite element analysis software ANSYS respectively according to the rigid, semi-rigid connection hinge and three kinds of modeling, structural dynamic properties are analyzed as follows: 3.1.
The connecting rigidity of rational choice is affected by many factors, such as the natural period of the structure, construction site predominant period; the region may be subjected to seismic excitation. 4 Conclusions The most important conclusions drawn from the present study are as follows: (1) The structure of semi rigid connections of low order mode vibration period increases significantly, and the higher mode of vibration period of impact is very small, can be neglected, the natural period of the structure change range, the maximum response volume from seismic excitation in different section, the structure design is unfavorable

In addition, adhesive bonding technique allows structural components with different mechanical and thermal properties.
The theoretical development of the model was presented and then numerical solutions of the governing equations for free vibration along with boundary and continuity conditions yielded the system natural frequencies, loss factors, and mode shapes.
It is also shown that the strength of the adhesive has a very significatant effect on the modal properties of the even modes of vibration but an insignificant effect on the modal properties of the odd modes of vibration[10].
The mechanical properties of the adhesive and adherends used in the investigations are listed in table.1.
The accelerometer mass does affect the natural frequencies of the single joint lap.

Introduction Ceramic materials have various inherent properties, such as high hardness, great thermal stability, chemical inertness and excellent wear resistance.
The properties parameters of alumina nitride ceramic are listed in table 1.
The properties parameters of silicon carbide are listed in table 2.
The properties of silicon carbide Material Density (kg/m3) Vickers hardness (GPa) Composition (%) SiC Fe2O3 SiC 3200 30-33 ＞97.5 ＜0.7 Fig.2 is the micrographs of the silicon carbide particle in this experiment.
In the experiments, six variable control factors are chosen, i.e. jet impact angle, standoff distance, water pressure, abrasive mesh number, traverse speed and vibration amplitude.

An improvement in water resistance of natural fibre composites would significantly enhance their qualities and mechanical properties [1], besides that water content affects the dielectric properties of composites to be used for insulation purposes.
Thermal Properties Of Lignocellulosic Filler-Thermoplastic Polymer Bio-Composites.
Part I: Effects on physical and mechanical properties.
Influence of strain rate on the flexural properties of a wood flour/HDPE composite.
Surface modified clay/polypropylene (PP) nanocomposites: Effect on physico-mechanical, thermal and morphological properties.

Implant materials with being bioactive and better mechanical properties are now demanded since too harder materials than bone, like metals and ceramics, are disadvantageous in causing malfunctions like loss of bone itself due to stress-shielding effects.
They suggested that Ormosils consisted of nano-sized silica clusters interconnected by the PDMS chains (Fig.4), and they controlled chemical and mechanical properties of the hybrids by changing the mixing ratios of TEOS and PDMS [30-33].
However, it is inferior in mechanical properties and too highly biodegradable for most medical applications.
Hence the polysaccharide chains should be cross-linked and networked to some extent, so that its mechanical properties are improved and has controlled biodegradability.
The mechanical properties of the hybrids depended on the content of GPTMS, increase of GPTMS give stiffening to the hybrids membrane.

Factors that affect the degree of deacetylation are temperature, time, base concentration, solution with solids, type of base, and the circumstances under which deacetylation is performed [12].
The thickened chitosan solution was also added with PANi to improve the mechanical properties of the chitosan film.
The chitosan film produced in this experiment is colorless and has mechanical properties that do not tear easily, but is not resistant to water.
Structure, properties and applications,” Mar.
Alizadeh, “Preparing chitosan–polyaniline nanocomposite film and examining its mechanical, electrical, and antimicrobial properties,” Polym.

Okuyucu researched the correlation between the friction stir welding parameters of aluminum plates and mechanical properties [7].
In this model, the process factors influencing the DEHS parameters are the welding current and the welding voltage.
The two factors form a two-dimension plane, and all points on the plane are available in the actual process.
(4) where 0<η<1, is the learning factor, yk is the output of hidden layer.
But it is imprecise because of the different welding processes and material properties.

Influence of Vanadium Microaddition on the Microstructure and Mechanical Properties of High Strength Large Diameter Wire-Rods L.
If an increase in the transformation temperature occurs a deleterious effect on toughness properties is expected.
Similarly, other factors, such as V microaddition, could have an effect on this size by modifying the nucleation process of pearlite [9].
The reduction in strength originated by the change in chemical composition can be compensated or even, increased by vanadium microaddition. ¾ Vanadium microalloying is affecting the interlamellar spacing in different ways: ƒ When added to C-Mn-Cr base steel, the interlamellar spacing increases as a consequence of higher transformation temperatures.
The rise in the transformation temperature does not affect the size of the crystallographic ferrite unit that controls brittle fracture propagation in pearlite

The multi-path fading is an important factor which affects the wireless channel capacity and the transmission quality.
Nonetheless, due to the affection of the power, quality and volume of the mobile terminal, many antennas are designed in base stations in actual mechanical process, so that the received actual improvements are far from what we have expected theoretically.
Agreement on cooperative diversity Cooperative diversity has various forms, and different forms are different in their complexity and properties.
Sendonaris A’s research indicates that coding cooperation prefers to sacrifice the users’ property of relatively good quality in the fast fading environment.
Of course, in certain environment, it needs to find the balance point between the property gain and the complexity.