Study on mechanical properties of kaolin-based geopolymer with various Si/Al ratio and aging time |
Binghuan Gao1, Seongwan Jang1, Hyeonjin Son1, Hee Jung Lee1, Hwan Jong Lee2, Jeong Jik Yang2, Chang-Jun Bae1 |
13D Printing Materials Center, Korea Institute of Materials Science (KIMS), Changwon 51508, Republic of Korea 2Korea Automotive Technology Institute, Gyeonggi 15041, Republic of Korea |
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Received: March 30, 2020; Revised: July 14, 2020 Accepted: August 10, 2020. Published online: November 30, 2020. |
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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. |
Key words:
Geopolymer · Si/al ratio · Flexural strength · Aging time |
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