Mechanical properties reduced stress

Recycled EVA/GRT powder blends of three particle sizes of greater than 200 turn, 200-500 turn, and greater than 500 p,m with concentrations up to 70 wt.% were prepared by using a Brabender mixer (Mujal-Rosas et al., 2011). The stress-strain behavior showed that upon the addition of smaller particles to the matrix up to 10%, the Young s modulus of the blends increased, while other mechanical properties reduced. At the higher concentration of GRT, all mechanical properties decreased. However, conductivity, permittivity, and dielectric loss factor of blends increased with the powder concentration. 

The advantages of the presence of nanoparticles in composites include reduced weight, improved mechanical properties, better stress transfer, reducing the amount of dead load in many applications, mainly automotive and aeronautical [1]. 

Acetate and triacetate exhibit moderate changes in mechanical properties as a function of temperature. As the temperature is raised, the tensile modulus of acetate and triacetate fibers is reduced, and the fibers extend more readily under stress (see Fig. 4). Acetate and triacetate are weakened by prolonged exposure to elevated temperatures in ah (see Fig. 5). 

Cooling rates can affect product properties in a number of ways. If the polymer melt is sheared into shape the molecules will be oriented. On release of shearing stresses the molecules will tend to re-coil or relax, a process which becomes slower as the temperature is reduced towards the Tg. If the mass solidifies before relaxation is complete (and this is commonly the case) frozen-in orientation will occur and the polymeric mass will be anisotropic with respect to mechanical properties. Sometimes such built-in orientation is deliberately introduced, such as... 

For values of Ild less than l/d)c, the tensile stress in the fiber is always less than that in the matrix. The transfer of load from the matrix to the fiber is poor and the mechanical properties of the fiber are not fully utilized. If lid > l/d)c, the tensile stress at the interface remains at a maximum over a greater proportion of fiber length. Here, the transfer of stress from the matrix to the fiber is very efficient, but the average tensile stress in the fiber is always less than that in the matrix because of reduced tensile stress at the end of the fiber. 

Monel, the classic nickel-copper alloy with the metals in the ratio 2 1, is probably, after the stainless steels, the most commonly used alloy for chemical plant. It is easily worked and has good mechanical properties up to 500°C. It is more expensive than stainless steel but is not susceptible to stress-corrosion cracking in chloride solutions. Monel has good resistance to dilute mineral acids and can be used in reducing conditions, where the stainless steels would be unsuitable. It may be used for equipment handling, alkalies, organic acids and salts, and sea water. 

The properties of PET can be modified by the incorporation of co-monomers. Typical examples of these are isophthalic acid (IPA) (influences stress cracking resistance and melting temperature), 2,6-naphthalene dicarboxylic acid (NDC) (improves mechanical properties and reduces gas permeability), cyclohexane... 

In the 1950 s an investigation into the effect of ultrasonic vibrations on the mechanical properties of metals showed that superimposing an alternating stress on a workpiece greatly affected the process rate and considerably reduced the force necessary for work-piece deformation [20]. 

Estimadon of liquidus and solidus temperatures of oxide inclusions in steels. The deformation of inclusions in steels has significant consequences on the hot workability of steels as well as for the mechanical properties of the final product. In order to increase their deformability there are at least three strategies (Matsumiya et al. 1987) (1), Reduction of their melting point (2), deceleration of crystallisation and (3), reducing their flow stress. If the melting point can be reduced sufficiently so that some liquid is present at the hot-working temperature, the inclusions would be expected to deform easily. 

Mechanical testing of the three-step cure specimens indicated that no sacrifice in properties resulted from the modification of the process cycle. The retainment of mechanical properties (transverse strength and modulus) coupled with the reduction in dimensionless curvature for the three-step cure cycles investigated provides another suitable cure cycle modification for reduction of residual stresses in composite materials. Overall processing time has not been increased beyond that specified in the MRC cycle. Thus, with no increase in process time and comparable mechanical properties, the residual stresses have been reduced by more than 20 percent in comparison to the MRC cycle baseline data. 

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