Tuning the Carbonation Resistance of Metakaolin–Fly Ash-Based Geopolymers: The Dual Role of Reactive MgO in Microstructure and Degradation Mechanisms
Abstract
1. Introduction
2. Experimental Programs
2.1. Raw Materials
2.2. Experimental Design and Specimen Preparation
2.3. Accelerated Carbonation Procedure
2.4. Testing Methods
2.4.1. Compressive Strength
2.4.2. Carbonation Depth
2.4.3. Material Alkalinity
2.4.4. MIP, XRD, and FTIR Measurements
3. Results and Discussion
3.1. Compressive Strength
3.2. Carbonation Depth
3.3. pH Value
3.4. Pore Structure
3.5. XRD Analysis
3.6. FT-IR Analysis
4. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Material | SiO2 | Al2O3 | CaO | Fe2O3 | MgO | K2O | Na2O | SO3 | TiO2 | Others |
---|---|---|---|---|---|---|---|---|---|---|
Metakaolin | 53.80 | 43.20 | - | 1.10 | 0.82 | 0.45 | 0.18 | - | - | 0.45 |
Fly ash | 57.96 | 31.14 | 3.02 | 3.86 | 0.52 | 2.03 | - | 0.64 | 0.52 | 0.31 |
Serial Number | MgO Content (%) | MK (%) | FA (%) | Alkaline Content (%) | Water/Binder Ratio |
---|---|---|---|---|---|
M10F0-0% | 0 | 100 | 0 | 10% | 0.63 |
M8F2-0% | 80 | 20 | |||
M6F4-0% | 60 | 40 | |||
M10F0-4% | 4 | 100 | 0 | 10% | 0.63 |
M8F2-4% | 80 | 20 | |||
M6F4-4% | 60 | 40 | |||
M10F0-8% | 8 | 100 | 0 | 10% | 0.63 |
M8F2-8% | 80 | 20 | |||
M6F4-8% | 60 | 40 |
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Li, S.; Ji, D. Tuning the Carbonation Resistance of Metakaolin–Fly Ash-Based Geopolymers: The Dual Role of Reactive MgO in Microstructure and Degradation Mechanisms. J. Compos. Sci. 2025, 9, 549. https://doi.org/10.3390/jcs9100549
Li S, Ji D. Tuning the Carbonation Resistance of Metakaolin–Fly Ash-Based Geopolymers: The Dual Role of Reactive MgO in Microstructure and Degradation Mechanisms. Journal of Composites Science. 2025; 9(10):549. https://doi.org/10.3390/jcs9100549
Chicago/Turabian StyleLi, Shuai, and Dongyu Ji. 2025. "Tuning the Carbonation Resistance of Metakaolin–Fly Ash-Based Geopolymers: The Dual Role of Reactive MgO in Microstructure and Degradation Mechanisms" Journal of Composites Science 9, no. 10: 549. https://doi.org/10.3390/jcs9100549
APA StyleLi, S., & Ji, D. (2025). Tuning the Carbonation Resistance of Metakaolin–Fly Ash-Based Geopolymers: The Dual Role of Reactive MgO in Microstructure and Degradation Mechanisms. Journal of Composites Science, 9(10), 549. https://doi.org/10.3390/jcs9100549