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Feasibility of alkali-activated mining waste foamed materials incorporating expanded granulated cork

Beghoura I., Castro-Gomes J., Ihsan H., Estrada N.

Mining Science

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2017

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Vol. 24

7--28

EN

Different combinations of mining waste mud, grounded waste glass, Portland cement, metakaolin and expanded cork were mixed together with alkaline activators (sodium silicate and sodium hydroxide solution) and as well aluminum powder or hydrogen peroxide to produce foamed lightweight materials. The size of the mineral materials is under 500 µm and expanded cork particles size is between 2 to 4 mm. The expanded cork added to the mixes changed between 10 to 40% volume of total solids. The influence of expanded cork on compressive strength was investigated. Precursors and activators were mixed together to produce a homogeneous mixture, which was placed into a cubic mold (40 x 40 x 40 mm3), and cured at a temperature of 60°C, for 24 hours. After curing process, samples without foaming agents achieved the maximum compressive strength of 14.7 and 19.5 MPa for 7 and 28 days respectively. The porosity was observed by the naked eye of large voids in a range of 4 mm in size. Microstructure analyses were carried on by SEM. Samples made with aluminum powder showed higher volume increase about 358% compared with samples made with hydrogen peroxide that presented a 141% volume increase. This preliminary study shows the feasibility to produce new improved lightweight foamed alkali activated materials incorporating expanded cork with potential applications in artistic, architectural, and historical heritage restoration.

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Energy absorption study of aluminium profiles with variety of filling configurations

Bogusz P., Stankiewicz M., Sławiński M.

Engineering Transactions

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2017

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Vol. 65, iss. 4

543--562

EN

The subject of this paper is research of thin-walled aluminium profiles filled with different materials and subjected to dynamic load. The aim of this study was to determine the crashworthiness capabilities of the tested elements. Such structures can be used as elements minimalising the effects of blast wave load on military vehicles and occupants carried thereon. The blast wave generated during the explosion of explosives, especially improvised explosive devices(IED), under or near a combat vehicle poses a deadly threat to the crew and passengers inside the vehicle. The idea of installing crashworthy structures in a vehicle seat to protect the crew and passengers is not new. It was found useful in aviation, automotive or railway industry. In this paper, circular aluminium profiles of an external diameter of 50 mm and thickness of 2 mm were investigated. They were filled with three kinds of materials: cork, foamed aluminium of low density and foamed aluminium of high density. The dynamic tests were performed on a spring hammer apparatus. The energy absorbing structures and materials used to fill the aluminium profiles were examined separately in static compression tests. The characteristics of force-displacement response of the investigated structures were determined, compared and analysed. The energy absorbing characteristic parameters were obtained and discussed to determine the best option.

3

Static axial crush performance of unfilled and foamed-filled composite tubes

Ochelski S., Bogusz P., Kiczko A.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2012

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Vol. 60, nr 1

31-35

EN

The use and the combination of new, high efficient materials for crashworthiness is of great interest nowadays. Foamed materials are commonly used to increase efficiency of composite materials. Based on the results obtained by Brachos and Douglas, it can be concluded that the sum of the energy absorption capabilities of the foamed filling and unfilled composite tubes is smaller than the energy absorbed by the tubes filled with the same filling. The paper presents the results of the experimental investigations into the influence of filling the tubes with different materials on the impact energy absorption capability. The tube shaped specimens made of epoxy composite, reinforced with carbon or glass fabrics were filled with foamed aluminium or foamed poly(vinyl chloride). It was proved that the foamed materials increase the energy absorption and the absorbed energy of the tubes filled with foams is greater than the sum of the energy absorbed by the composite tube without filling and the foamed material itself investigated separately, when the wall thickness is more than 2 mm. The investigations of the filled tubes with the thickness of walls equal to 1 mm showed lower absorbed energy values because the crushing force had decreased during the crush. The investigations were executed to show what are the effects of filling composite energy absorbing elements in the shape of tubes with foamed materials. Additionally, influence of tube wall thickness and crush mechanism were studied.

4

Spieniona ceramika

Dąbrowski K.

Szkło i Ceramika

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2010

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R. 61, nr 1

35-37

PL

Nowoczesne materiały ceramiczne dzięki swoim unikalnym właściwościom (odporność na wysoką temperaturę, narażenia klimatyczne i chemiczne, twardość i wytrzymałość mechaniczna, mała masa i małe tarcie) znajdują coraz szersze zastosowanie.