Effect of curing time on thermal response characterization of carbon-nano cementitious composites. (1st June 2021)

• Record Type: Journal Article
• Authors: Lee, Heeyoung; Seong, Jongkyeong; Chung, Wonseok
• Is Part Of: Composite structures. Volume 265(2021)
• Publication Date: 2021-06-01
• Subjects: CNT carbon nanotube -- MWCNT multi-walled CNT -- CNF carbon nano fiber -- FE-SEM field emission -- TGA thermogravimetric analysis -- XRD X-ray diffraction; Multi-walled carbon nanotube (MWCNT) -- Heating performance -- Cementitious -- Dry curing condition -- Field emission scanning electron microscopy (FE-SEM) -- Thermogravimetric analysis (TGA) -- X-ray diffraction (XRD); Composite construction -- Periodicals; Composites -- Périodiques; 624.18
• DOI: 10.1016/j.compstruct.2021.113781
• Languages: English
• ISSNs: 0263-8223

Abstract

Highlights: Heat generation of MWCNT cementitious composites increase with curing time. MWCNT composites exhibit better heat generation at higher MWCNT concentrations. Current flow in MWCNT composites is proportional to heat generation performance. Thermal decomposition temperature of MWCNTs was 750 °C or more. MWCNTs had no effect on the hydrates generated inside the MWCNT composites. Abstract: Introducing small amounts of multi-walled carbon nanotubes (MWCNTs) into cement-based materials changes the thermal and electrical characteristics of the composites. The heat generation of cement materials can be enhanced by incorporating MWCNTs. The thermal response of cement composites incorporating MWCNTs under dry curing conditions was experimentally investigated by varying the curing time and MWCNT concentrations of the composite. The temperature change in each specimen was measured by connecting the electrode to the power supply and supplying a constant voltage. The heat generation of the MWCNT cementitious composite increased with the number of curing days. In addition, the heat generation of the composite increased in a quadratic form with increasing MWCNT concentration. The electrical resistance of the composite depended on the progress of the hydration reaction. In the case of cementitious composites containing relatively high concentrations of MWCNTs, the electrical resistance decreased as the number of curing days increased.