Wyniki wyszukiwania - Biblioteka Nauki

1

Mechanical Behavior of Aluminum Phosphide under Pressure

100%

Daoud S.

|

nr 1

23-27

EN

With the help of structural parameters and elastic constants obtained previously in our work (S. Daoud, N. Boiud, N. Lebga, J. Optoelectron. Adv. Mater. 16, 207 (2014)), different empirical formulae were successfully used to investigate: equation of state, the isotropic shear modulus, the Young modulus, the Cauchy ratio, the Born ratio, the Poisson ratio, the Pugh ratio, the Kleinman parameter, and the converse piezoelectric coefficient of the aggregate AlP material with cubic zinc-blende structure under pressure up to experimental pressure of phase transition (9.5 GPa). In addition, the Debye temperature at equilibrium volume was predicted, the result obtained is in excellent agreement compared to the experimental ones, the deviation is less than 1.4%.

2

Investigating the Effect of Photo-Oxidative Degradation on the Ageing Resistance of the Car Mudflaps Manufactured with Post-Production High-Density Polyethylene Wastes

63%

Czarnecka-Komorowska D. , Swain C. , Kopeć B. , Borowski J. , Garbacz T.

|

tom Vol. 16, no 4

38--47

EN

The paper presents the results of the ageing resistance of automotive mudflaps made of recycled polyethylene blends. The mudflaps were manufactured by a plastic sheet extrusion-calendaring process in Novotech Kostrzyn nad Odrą company. The changes of the mechanical properties in the tensile test and impact toughness test as well as in Shore hardness due to the accelerated aging process were characterized, taking into account the aging sensitivity coefficient (KI), and changes in the structure within the wavenumber range 4000-400 cm-1, taking into account the CI coefficient. The results showed a higher melting point and crystallinity for the recycled HDPE blends during photo-oxidative degradation. Moreover, the results presented decreased tensile strength and ductility, due to macromolecular chain scission caused by oxidation. It was found that the blends of HDPE based on recycled materials are more sensitive to the aging process than virgin HDPE. Finally, it can be concluded that the sensitivity to ageing blends increases with the increase of recycled HDPE content in the HDPE matrix.

3

Structural optimization of internally reinforced beams subjected to uncoupled and coupled bending and torsion loadings for industrial applications

51%

Silva H. M. , Meireles J. F.

|

tom Vol. 21, nr 2

329--351

EN

In this work, novel types of internally reinforced hollow-box beams were structurally optimized using a Finite Element Updating code built in MATLAB. In total, 24 different beams were optimized under uncoupled bending and torsion loads. A new objective function was defined in order to consider the balance between mass and deflection on relevant nodal points. New formulae were developed in order to assess the efficiency of the code and of the structures. The efficiency of the code is determined by comparing the Finite Element results of the optimized solutions using ANSYS with the initial solutions. It was concluded that the optimization algorithm, built in Sequential Quadratic Programming (SQP) allowed to improve the effective mechanical behavior under bending in 8500%, showing a much better behavior than under torsion loadings. Therefore, the developed algorithm is effective in optimizing the novel FEM models under the studied conditions.

4

Structural optimization of internally reinforced beams subjected to uncoupled and coupled bending and torsion loadings for industrial applications

51%

Silva H. M. , Meireles J. F.

|

2017

|

tom Vol. 21, nr 3

731--753

EN

In this work, novel types of internally reinforced hollow-box beams were structurally optimized using a Finite Element Updating code built in MATLAB. In total, 24 different beams were optimized under uncoupled bending and torsion loads. A new objective function was defined in order to consider the balance between mass and deflection on relevant nodal points. New formulae were developed in order to assess the efficiency of the code and of the structures. The efficiency of the code is determined by comparing the Finite Element results of the optimized solutions using ANSYS with the initial solutions. It was concluded that the optimization algorithm, built in Sequential Quadratic Programming (SQP) allowed to improve the effective mechanical behavior under bending in 8500%, showing a much better behavior than under torsion loadings. Therefore, the developed algorithm is effective in optimizing the novel FEM models under the studied conditions.