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In the metal plastic forming process, ductile fracture is an important factor influencing the forming properties of materials, and the ductile fracture criterion can effectively predict the moment and location when the material fracture.
However, the material constants in ductile fracture criterion is related to many complex factors such as material properties, forming process, stress and strain state.
The tensile properties and the fracture strain of the material can be obtained through uniaxial tensile test or plane-strain tension tests, so the stress, strain and other related parameters in criteria can be converted into known constants of tensile properties combined with relevant plastic theory knowledge, then integrating the Eq. 1 to determine the material constants in criterion.
According to the number of unknown parameters in the Cockcroft-Latham, Brozzo, Oyane, and Clifte criterion, Takuda et al. [4] carried out uniaxial and plane-strain tension test for sheet specimens, obtained the tensile properties (including anisotropic coefficient) and fracture strain.
However, for the general material in the forming process, it is susceptible to the drawing speed, mold clearance, sharpness of the punching tool and other process factors, resulting in the material tending to appear necking, and the deformation path is not same after the material necking.

Fully deformed zone (100x) (b).Heat affected zone (200x) Fig.5.
[3] Sahin Mumim (2007) Evaluation of the joint interface properties of austenitic stainless steel joined by friction welding.
[4] P.Sathiya, S.Aravindan, A.Noorul Haq (2005); Mechanical and metallurgical properties of friction welded AISI 304 austenitic stainless steel, Int.
[5] D.Ananthapadmanaban (2009); A study of mechanical properties of friction welded mild steel to stainless steel joints, Mater.
[8] Afes Hakan, Turker Mehmet, Kurt Adem (2007); Effect of friction pressure on the properties of friction welded MA956 iron based super alloy.

However, the factors influencing the damage behaviour and the degradation of mechanical properties under real applications are numerous.
It is assumed that all planes perpendicular to the isotropic plane transversal to fiber direction possess the same properties [10].
These four material properties are essential for any non-isotropic engineering stress calculation, FE analysis etc. [10].
As a matter of fact, the applied load speed affects the measured mechanical properties and consequently any subsequently performed fatigue-life calculation.
Mechanical properties in fiber direction, transversal to fiber direction and under shear loads were created in experimental tests.

Based on a variation of important process factors, a polynomial regression modelis derived to fit the data.
Anyhow, also a correlation between kL and kz is visible which stands for a coupling of both properties.
In order to unite this criterion with maximizing kz, weighing factors for each criterion are commonly introduced.
The presented method can be transferred to controlling both, axial and lateral stiffness or other properties.
A major limitation is the coupling of the desired properties, i. e. the axial stiffness cannot freely be manipulated without affecting the lateral stiffness.

It was estimated that over 90% of all melt-blown (MB) nonwoens were made from polypropylene (PP), because of its low cost, ease of processing, good mechanical properties, lack of heat shrinkage, chemical inertness, and its ability to be drawn into very fine fibers.
Among them, Poly(lactic acid) (PLA) appear to be the most attractive because of high mechanical properties, thermal plasticity, fabric ability, and biocompatibility[2].
Liu reported [3] the influence of production processing on the structure, morphology, and mechanical properties of PLA MB.
Rheological behavior of polymers is one of the important factors affecting processability and the properties of final products.
However, few researchers have focused on the study of rheological properties of PLA and PLA composites for MB nonwoven.

This makes their numerical implementation difficult and may affect the efficiency of the time-domain BEM.
The symmetry properties of the fundamental solutions (22)-(24) are utilized to enhance the efficiency of the present Galerkin-method and to reduce the numerical cost to the level of the collocation method.
The following contraction index notation is used for the material properties Cijkl → Cαβ, elij → elα, hlij → hlα, (55) where α = { i if i = j 9 − (i + j) if i ̸= j , β = { k if k = l 9 − (k + l) if k ̸= l
As discussed in the first example, the normalized dynamic intensity factors start from a non-zero value for the investigated combined electrical and mechanical impact loading.
In the special case of a static loading the maximum electrical and magnetic intensity factors are obtained for the impermeable crack-face boundary condition while for a transient dynamic loading the electrical and magnetic intensity factors increase with the electrical permittivity and the magnetic permeability for a pure mechanical loading.

Problem such as wear and tear of PDC cutter are some of the main factors in drilling process failure affecting the rate of penetration (RoP).
There are several factors affecting rate of penetration but this research focus on rapid product development and changes to drill bit design for improvement in rate of penetration using reverse engineering approach.
Step of step for development of finite element analysis of PDC drill bit is as following: Define the properties of drill bit and formation in engineering data.
Table 2: Engineering Data for Analysis [9] Material Properties Limestone Density (2600 kg m^-3), Tensile ultimate strength (4.0e+06 Pa), Young’s Modulus (5.e+010 Pa), and Poisson’s Ratio (0.22).
Increasing number of cutters will decrease efficiency of cleaning hence affecting directly rate of penetration.

Mica can improve products electrical properties, heat resistance, cracking resistance and moisture resistance, and in the liquid resin system has good resistance to caking property.
Quartz powder has low thermal expansion and good electrical insulation properties, can improve the dimensional stability and thermal conductivity of the products, improve the dielectric properties of.
In the actual choice of initiator, should consider the following factors; resin mixture in the mold of liquidity, applicable period, responsiveness, product appearance and gloss, monomer residues and products of physical and mechanical properties.
Choose the appropriate color, but also play to improve the product durability, mechanical strength and optical properties of other benefits.     
Conclusion Choice of packing should be considered when the products performance, molding process and cost of several factors.

Introduction Fiber placement route modeling process is a complex one including multiple sections, affected by numerous factors, and with a vast area of involvement.
Especially the complex components surface, the coupling relationship of the geometry structure of component surface, materials and the mechanical properties of placement layers must be taken into account in the meantime.
Blom has put forward geodesic algorithm used to plan placement route of component with revolted surface, but it is not enough to study the placement route planning only by the surface features for aviation component and wind turbine blades and other components with complex curved shape, because it will cause great gap between fiber placement direction and mechanical direction of placement layers, which may lower the structure properties of components [2].
Since the tow band very thin (0.125-0.2mm), doesn’t affect the placement feasibility of fiber tow, but will bring about bending deformation of the fiber tow in the width direction and affect the placement feasibility [4].
Thus, is obtained by the triangle circumcircle properties

The current research focuses on the matrix gradation asphalt mixture design and optimization of the ratio of cement mortar, but few studies on how the interface affect to semi-flexible pavement materials properties[3] .Semi-flexible pavement material was a combination of organic and inorganic composite materials, the nature of the interface to semi-flexible pavement directly affect its mechanical properties and road performance.
In order to get excellent mechanical properties and pavement performance for semi-flexible pavement material, matrix mix asphalt mixture design was particularly important.Here we used the volume design method of asphalt mixture, by adjusting the rates pass through 4.75mm and 2.36mm these two key sieve [7], designed for the 30% porosity matrix asphalt mixtures, gradation curve shown in Figure 1.
The author studied the semi-flexible interfacial modifier’s shear properties , anti-fatigue properties, low temperature bending properties and dynamic modulus to determine its’ optimal dosage.He used the volume method of asphalt mixture to designe for the 30% porosity matrix asphalt mixtures,then poured cement mortar into it with different mass ratio interfacial modifier, which met the 28d compressive strength of 30MPa with good fluidity (11.87s) ;analysis of interfacial modifier on the shear properties of composite materials, anti-fatigue properties, low temperature bending properties and dynamic modulus results, to determine the optimal dosage of interfacial modifier.
Composite modulus was a method to describe the viscoelastic properties of asphalt mixture.
With the increase of interfacial modifier content, the overall properties of the semi-flexible pavement material were improved, taking economic factors into account, the best content of interface modifier was 0.4 to 0.6%.