Behaviour of aluminum foam under fire conditions

• Autorzy: Grabian J. , Gawdzińska K. , Szweycer M.
• Języki publikacji: EN

Abstrakty

EN

Taking into account fire-protection requirements it is advantageous for aluminum foam, after melting at a temperature considerably exceeding the melting point, to have a structure of discontinuous suspension of solid inclusions to liquid metal instead of liquid consistency. Continuity of the suspension depends on the solid phase content. The boundary value of the phase determined by J. Śleziona, above which the suspension becomes discontinuous, is provided by the formula (1). Figure 1 presents the relationship graphically. Boundary values of the v_s content resulting from the above relationship is too low, taking into account the data obtained from the technology of suspension composites [4]. Therefore, based on the structure assumed for the suspension shown in Figure 2 these authors proposed another way of determining the contents, the value of which is determined by the relationship (3) [5]. For purposes of the experimental study presented in the paper two foams have been molten: a commercially available one, made by aluminum foaming with titanium hydride, and a foam manufactured in the Marine Materials Plant of the Maritime University of Szczecin by blowing the AlSi7 +20% SiC composite with argon. Macrophotographs of foam cross-sections are shown in Figure 3. The foams have been molten in the atmosphere of air at a temperature of 750°C. The products of melting are presented in Figure 4. It appears that molten aluminum foam may have no liquid consistency, being unable to flow, which is a desired property from the point of view of fire-protection. The above feature of the molten foam results from the fact that it may be a discontinuous suspension of solid particles in a liquid metal. The suspended particles may be solid particles of the composite that served for making the foam or oxide membranes formed on extended metal surface of the bubbles included in the foam. The desired foam ability to form a discontinuous suspension after melting may be intensified by insertion of solid particles into the metal serving for foam formation.

Słowa kluczowe

EN

aluminium foam; suspensions; melting point

PL

piana aluminiowa; zawiesina; punkt topienia

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2008
• Tom: Vol. 8, iss. 2
• Strony: 41--44
• Opis fizyczny: Bibliogr. 5 poz., rys., wykr.

Twórcy

autor

Grabian J.

autor

Gawdzińska K.

autor

Szweycer M.

• Institute of Basic Technical Sciences, Maritime University of Szczecin, ul. Podgórna 51/53, 70-205 Szczecin,

Bibliografia

• [1] J. Banhart, M.F. Ashby, N.A. Fleck, Cellular Metals and Metal Foaming Technology, Proceedings of the 2nd International Conference on Cellular Metals and Metal Foaming Technology (MetFoam 2001), Bremen (Germany), 18 - 20.06.2001 r.
• [2] J. Sobczak, Piany metalowe monolityczne i kompozytowe oraz gazary, Instytut Odlewnictwa, Kraków 1998.
• [3] J. Śleziona, Kształtowanie właściwości kompozytów stop Al - cząstki ceramiczne wytwarzanych metodami odlewniczymi, Zeszyty Naukowe nr 1258, Politechnika Śląska, Gliwice 1994.
• [4] J. Sobczak, Kompozyty Metalowe, Instytut Odlewnictwa, Instytut Transportu Samochodowego, Kraków-Warszawa 2001.
• [5] J. Jackowski, M. Szweycer, D. Witczak, The Role of Capillary Phenomena During Consolidation of Non-Metallic Inclusions extracting Slag, Mat. II Międzynarodowej Konferencji "High Temperature Capillarity, Kraków 1997 (wydanie 1998), str. 374-379.