用石墨烯-碳纳米管混合体增强的砂的高温性能
1China Railway Construction Group Co., Ltd, East China Engineering Co., Ltd, Suzhou, China.
Science progress
|February 26, 2026
概括
混合碳纳米材料,包括石墨烯纳米板和碳纳米管,提高水泥砂的强度和耐高温. 这种混合方法增强了分散性,从而产生了优越的机械性能和微观结构的精细化.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 纳米技术纳米技术
背景情况:
- 基于水泥的材料在高温下容易降解.
- 提高纳米材料在水泥复合材料中的分散性是一项挑战.
- 石墨烯纳米板和碳纳米管提供了提高材料性能的潜力.
研究的目的:
- 调查混合石墨烯纳米板和碳纳米管的可行性,以改善在水泥砂中的分散.
- 评估这种混合纳米材料在暴露于高温后对砂的剩余机械性能的影响.
- 描述改性水泥砂的微观结构和孔隙结构.
主要方法:
- 在低质量分数 (≤0.15%) 的情况下将石墨烯纳米板和碳纳米管混合物纳入基于水泥的砂中.
- 将砂标本暴露在持续升高的温度下,温度高达600°C.
- 在冷却后测试剩余的机械性能 (压力和屈曲强度).
- 使用X射线衍射,扫描电子显微镜和侵入孔径学进行表征.
主要成果:
- 与基准组相比,混合纳米材料显著提高了压力和强度,分别提高了37%和28%.
- 含有混合纳米材料 (G5C10组) 的砂在暴露于400°C后表现出优异的性能,压力强度比参考强度高33%.
- 微观分析证实,混合结构抑制了纳米材料聚合,导致更好的分散,更密集的微观结构和精细的孔隙结构.
结论:
- 混合石墨烯纳米板和碳纳米管是改善水泥砂中纳米材料分散的有效策略.
- 增强的分散导致更好的机械性能和显著的延迟强度损失在高温下.
- 精致的微观结构和孔隙结构是混合水泥砂在高温下性能改善的关键因素.
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