Corrosion Studies of Fly Ash and Fly Ash-Slag Based Geopolymer

International Conference on Innovative Research - ICIR Euroinvent 2017

Zainal, F.F.^1 ; Amli, S.F.M.^1 ; Hussin, K.^1,2 ; Rahmat, A.^1 ; Abdullah, M.M.A.B.^1,2

Center of Excellence Geopolymer and Green Technology (CEGeoGTech), School of Materials Engineering, Universiti Malaysia Perlis (UniMAP), Perlis, Malaysia^1

Faculty of Engineering Technology, Universiti Malaysia Perlis (UniMAP), Perlis, Malaysia^2

关键词: Alkaline activators;    Aluminosilicate inorganic polymers;    Corrosion studies;    Morphological structures;    Morphology analysis;    Open circuit potential;    Reinforcement bar;    Slag-based geopolymer;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/209/1/012026/pdf
DOI  :  10.1088/1757-899X/209/1/012026

来源: IOP

【 摘 要 】

This paper presents the results of corrosion studies between Fly Ash Geopolymer (FG) paste and Fly Ash-Slag Geopolymer (FSG) paste. Geopolymer was made from aluminosilicate inorganic polymers mixed with the alkaline activator in order to reduce the carbon dioxide (CO2) to the ecosystem. Samples then were cured at 60°C for 24 hours in the oven. Reinforcement bar is placed at the center of the paste. The samples were examined after 7, 14 and 28 days in terms of Open Circuit Potential (OCP) test, phase analysis and morphology analysis. The potential values regarding OCP test for FSG paste from 7 days until 28 days are 0.464 V, 0.474 V and 0.498 V more positive than FG paste which the potential values are 0.087 V, 0.133 V and 0.206 V respectively. From the Pourbaix diagram, all the potential values for FG paste and FSG paste were located in the same Fe2O3, passivity region. Passive layer which is the oxide form exists in this region to protect the reinforcement bar from corrosion agents. It can be proved from phase analysis results which iron oxide hydroxide (FeOOH), hematite (Fe2O3) and magnetite (Fe3O4) peaks exist. The differences of morphological structures of these pastes were observed by Scanning Electron Microscope (SEM). It shows that FSG paste had good corrosion resistance and low corrosion rate compared to FG paste.