ESTUDO PRELIMINAR DO USO DOS FINOS DO RESÍDUO DA AREIA VERDE DE FUNDIÇÃO NO DESENVOLVIMENTO DE PASTAS GEOPOLIMÉRICAS
DOI:
https://doi.org/10.46421/entac.v18i.1039Keywords:
Green Foundry Sand Waste, Geopolymers, Compressive strenghtAbstract
In the process of casting metal parts, the molds are produced with a mixture of natural sand and bentonite, however, after heating, the activated bentonite loses its binding properties, causing part of the foundry sand to be discarded from the process. Aiming then to reuse the green foundry sand waste (GFSW) that is discarded in the metal smelting process, the present work had as main aim to evaluate the possibility of replacing the metakaolin with the GFSW fines in the development of a geopolymeric material. Five levels of substitution were studied (0%, 25%, 50%, 75% and 100%). The geopolymers were synthesized using an alkali percentage of 20%, a silica module of 0.5 and a water/solid ratio of 0.45. The specimens were submitted to the compressive strength test for three different cure times (7, 14 and 28 days). The results showed that when replacing the metakaolin by GFSW, the compressive strength decreased significantly, but adjustments in the curing process and in the compositions of the activators can improve the results allowing the use of GFSW in the development of geopolymers.
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