Manufacturing Technology 2013, 13(1):68-73 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/68

Modified hydrated sodium silicate as a modern binder for ecological moulding sands

Katarzyna Major-Gabryś, Stanisław M. Dobosz, Jarosław Jakubski

AGH University of Science and Technology, Faculty of Foundry Engineering, Department of Moulding Materials, Mould Technology and Foundry of Non-ferrous Metals, Al. A. Mickiewicza 30, 30-059 Krakow, Poland

This article is devoted to ecological moulding sands with hydrated sodium silicate as binder. The inorganic nature of the binder results in poor knock-out properties and low ability to mechanical reclamation of tested moulding sands. In the present study authors focused on developing a new addition to the composition of these environmental friendly foundry moulding sands, providing them better knock-out properties. The analysis of the literature data let authors focus on the use of additives containing Al2O3 as components of moulding sands with hydrated sodium silicate. These additives provide better knock-out properties of moulding sands measured according to retained strength Rctk and also lead to lower thermal expansion of moulding sands. The authors have developed a new supplement containing Al2O3 and demonstrated its positive impact on moulding sand with hydrated sodium silicate knock-out properties.

Keywords: moulding sand, hydrated sodium silicate, phase gamma Al2O3 (γ-Al2O3 phase), thermal expansion, knock-out properties

Published: March 1, 2013  Show citation