在干燥合体悬浮液时,裂密度加大.
Paul Lilin1, Mario Ibrahim1, Irmgard Bischofberger1
1Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Science advances
|September 11, 2024
概括
干燥的合液滴由于内部应力而形成裂. 裂间距取决于沉积物厚度,裂形状与沉积物有关.
科学领域:
- 合体和表面科学科学
- 材料科学 材料科学 材料科学
- 复杂系统的物理 复杂系统的物理
背景情况:
- 水性合体悬浮液的滴在干燥时形成密集的颗粒沉积物.
- 蒸发驱动矿床内的辐射水流,产生负孔压.
- 这种孔隙压力会产生拉力干燥应力,导致裂形成.
研究的目的:
- 为了合理化裂传播和密集化在体沉积干燥过程中的动态.
- 为了建立干燥应力,裂形成和沉积形态之间的关系.
- 了解控制干燥合膜中断裂动态的能量平衡.
主要方法:
- 裂传播和密集化动态的分析.
- 当地能源平衡模型的应用.
- 研究弹性能量,断裂成本和孔隙压力之间的相互作用.
主要成果:
- 裂纹密度随着干燥的进展而和.
- 最终的辐射裂间距与当地的沉积物厚度成正比.
- 裂纹段面积比是由沉积物的整体形状决定的.
结论:
- 这项研究为了解干燥体悬浮液中的裂纹形成提供了一个框架.
- 这些发现为控制薄膜裂纹模式提供了洞察力.
- 这项工作对制造有图案的材料和了解自然干燥过程有影响.
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