Wyniki wyszukiwania - BazTech

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Experimental and numerical analysis of aluminum alloy AW5005 behavior subjected to tension and perforation under dynamic loading

Bendarma A., Jankowiak T., Łodygowski T., Rusinek A., Klósak M.

Journal of Theoretical and Applied Mechanics

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2017

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Vol. 55 nr 4

1219--1233

EN

The paper describes mechanical behavior of aluminum alloy AW5005 (EN AW5005) under impact loading. The work is focused on tensile tests and the process of perforation of aluminum alloy AW5005 sheets. Experimental, analytical and numerical investigations are carried out to analyse in details the perforation process. Based on these approaches, ballistic properties of the structure impacted by a conical nose shape projectile are studied. Different failure criteria are discussed, coupling numerical and experimental analyses for a wide range of strain rates. Optimization method functions are used to identify the parameters of the failure criteria. Finally, good correlation is obtained between the numerical and experimental results for both tension and perforation tests.

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Analysis of the composite material behaviour subjected to dynamic bending using the hopkinson bar

Massaq A., Rusinek A., Klósak M., Boulouz A., Koutti L.

Engineering Transactions

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2016

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Vol. 64, iss. 1

115--131

EN

The aim of this study is to propose an experimental approach supported by an analytical analysis for polymer materials under dynamic loading. The experimental technique of Hopkinson split pressure bar is used which allows for high impact velocities. The specimens are subjected to the three-point bending and the efficiency of the experimental technique is proved. During quasi-static and dynamic bending tests, the rupture mode is described and the evolution of the energy and the ultimate stresses as a function of the initial impact velocity is discussed. In addition, the critical impact velocity estimated above an important change in the rupture mode is observed. In order to better describe the physical phenomena encountered during the three-point bending impact, the analysis is supported by a rheological model based on a mass-spring system.

3

Challenges of Innovation in the Developing Countries. The Need for Engineers' Education

Klósak M., Majdouline I.

Logistics and Transport

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2014

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Vol. 24, No. 4

45--48

EN

There has never been any doubt about the importance of promoting innovation that speeds up the development of all domains of our lives. Processes, services, products, everything needs to be improved in a permanent way. However, to innovate means to make effort. Kline has proposed a chain-linked model that describes the innovation process. The market need is the main source to innovate, but a proper interaction between production, marketing and R&D is required to dynamise innovation. The performance of innovation can be measured by the number of patents, R&D applications or professional literature citations

4

New Experimental Technique for Dynamic Bending of Composite Materials

Massaq A., Rusinek A., Klósak M.

Engineering Transactions

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2014

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Vol. 62, iss. 3

269–-289

EN

The paper is reporting a new experimental technique to study the dynamic behaviour of composite materials subjected to bending direct impact. It is based on the Hopkinson bar system allowing to observe material behaviour at very high impact velocities. The material used to perform the tests is a woven glass-fibre-reinforced Polyamide 6.

5

Method for Determination of the Dynamic Elastic Modulus for Composite Materials

Massaq A., Rusinek A., Klósak M.

Engineering Transactions

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2013

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Vol. 61, iss. 4

301--315

EN

Majority of polymer matrix composite materials, a marked viscoelastic behavior and faculties of dissipation of energy, it thus proves necessary to know the viscoelastic properties, as the dynamic Young modulus. In this work, we will present a new experimental technique for determining the dynamic elastic modulus at high strain rates of polymer matrix composites materials by a statistical method demanding a large number of tests. This new technique is based on the split Hopkinson pressure bar. Further, we study the effect of strain rate on dynamic elastic modulus of a woven Polyamid 6 – glass fibre reinforced.