砂和NMR放松计数据的可打印描述符之间的关系
Mihai M Rusu1,2, Ioan Ardelean1,2
1Department of Physics and Chemistry, Technical University of Cluj-Napoca, 400114 Cluj-Napoca, Romania.
Materials (Basel, Switzerland)
|July 12, 2025
概括
这项研究将混凝土的打印能力与核磁共振 (NMR) 数据联系起来. 低场NMR放松计揭示了砂的打印窗口和毛孔结构发展之间的相关性,有助于建筑标准化.
科学领域:
- 材料科学 材料科学 材料科学
- 建筑工程工程 建筑工程
- 化学工程是化学工程的重要组成部分.
背景情况:
- 混凝土印刷对于现代建筑至关重要,但缺乏标准化的表征工具.
- 混凝土材料的可打印性受到质学和早期水分的影响.
- 核磁共振 (NMR) 放松计为材料特性提供了非破坏性的洞察力.
研究的目的:
- 为了确定混凝土可打印性描述符和低场NMR放松度数据之间的相关性.
- 调查烯酸超级增塑剂和酸加速剂对砂性能的联合作用.
- 探索NMR在印刷混凝土中特征结构积累的潜力.
主要方法:
- 准备了固定比例的白色波特兰水泥,细型聚合物和烟的砂.
- 使用挤出测试和光纤的视觉检查来评估可打印性,以确定打印窗口.
- 低场NMR放松计被用于测量横向 (T2) 和纵向 (T1) 放松时间.
主要成果:
- 超级塑化剂和加速器都增强了砂的打印窗口.
- 酸加速器在30-60分钟的加水后加速了毛细血管毛孔 (S/V) 的特定表面积的增加.
- 在打印窗口和横向放松率 (1/T2) 和S/V.的线性增长范围之间确定了相关性.
结论:
- 低场NMR放松计显示,在打印过程中对水泥材料结构积累的特征有前途.
- 核磁共振数据可以与关键的可打印描述符联系起来,从而促进对混凝土印刷的标准的制定.
- 该研究强调了NMR作为混凝土增材制造中的质量控制和流程优化工具的潜力.
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