VSE knjižnice (vzajemna bibliografsko-kataložna baza podatkov COBIB.SI)
  • Characterization of geopolymer fly-ash based foams obtained with the addition of Al powder or H2O2 as foaming agents
    Ducman, Vilma ; Korat, Lidija, 1986-
    Recent innovations in geopolymer technology have led to the development of various different types of geopolymeric products, including highly porous geopolymer-based foams, which are formed by the ... addition of foaming agents to a geopolymer fly-ash based matrix. These agents decompose, or react with the liquid matrix or oxygen in the matrix, resulting in the release of gases whichform pores prior to the hardening of the gel. The hardened structure has good mechanical and thermal properties, and can therefore be used for applications in acoustic panels and in lightweight pre-fabricated components for thermal insulation purposes. This study presents the results of the pore-forming process in the case when two different foaming agents, i.e. aluminium powder amounting to 0.07, 0.13 and 0.20 mass. % and H2O2 amounting to 0.5, 1.0, 1.5 and 2.0 mass. %, were added to a fly-ash geopolymer matrix. The physical, mechanical, and microstructural properties of the thus obtained foams, and the effects of the type and amount of the added foaming agent, are presented and discussed. Highly porous structures were obtained in the case ofboth of the investigated foaming agents, with overall porosities up to 59% when aluminium powder was added, and of up 48% when H2O2 was added. In the latter case, when 2% of the H2O2 foaming agent was added, finer pores (with diameters up to 500 Žm) occurred in the structure, whereas somewhat larger pores (some had diameters greater than 1 mm) occurred when the same amount of aluminium powder was added. The mechanical properties of the investigated foams depended on their porosity. In the case of highly porous structures a compressive strength of 3.3 MPa was nevertheless achieved for the samples containing 0.2% of aluminium powder, and 3.7 MPa for those containing 2.0% of H2O2.
    Vir: Materials characterization. - ISSN 1044-5803 (Vol. 113, 2016, str. 207-213)
    Vrsta gradiva - članek, sestavni del ; neleposlovje za odrasle
    Leto - 2016
    Jezik - angleški
    COBISS.SI-ID - 2168679