Study on mechanical properties of kaolin-based geopolymer with various Si/Al ratio and aging time

다국어 초록 (Multilingual Abstract)

Geopolymers are a class of aluminosilicate-based ceramics that contain 3D network synthesized by condensation of tetrahedral aluminosilicate units, produced by the aluminosilicate raw materials and alkaline activators. The Si/Al ratio and aging time are the crucial parameters which infl uence the reaction degree of geopolymerization process and the reaction time, aff ecting the fi nal properties, respectively. Here, we investigated the eff ect of Si/Al ratio and aging time on the microstructure and mechanical properties of kaolin-based geopolymers, where SEM, XRD, and piston on three ball test were applied at the diff erent Si/Al ratio and the aging time. Given the higher ratio of Si/Al and longer aging time, geopolymer-based matrix was densifi ed and high crystalline phases were evolved. Furthermore, the highest fl exural strength of specimen, with the Si/ Al ratio of 2.49 and aging time of 1 day, was 19.5 MPa.

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