脱水导致易碎水凝的结损伤
Shaohua Yang1,2, Dominic Gerber2, Yanxia Feng2
1School of Mechanical Engineering and Automation, Beihang University, Beijing, China.
Science advances
|August 23, 2024
概括
结破坏材料不是通过膨胀,而是通过冰的增长导致脱水. 这种冷过程导致干燥诱导的骨折,类似于干燥裂纹.
科学领域:
- 材料科学 材料科学 材料科学
- 物理 物理学 物理
- 物理化学 物理化学
背景情况:
- 众所周知,结会损害软湿的材料,但其潜在机制尚不清楚.
- 了解结损害对于冷保存,食品科学和升的应用至关重要.
- 现有的理论通常将损害归因于水膨胀或冰腔压力.
研究的目的:
- 为了阐明易碎水凝中结诱导损伤的机制.
- 调查冰的增长和水运输在物质断裂中的作用.
- 为了建立冰损伤和干燥裂纹之间的类比.
主要方法:
- 在冷过程中观察模型水凝样本中冰填充裂纹的传播.
- 使用受控结实验来分析断裂力学.
- 应用冷和脱水原理来解释结果.
主要成果:
- 结损伤不是由于水膨胀或来自冰洞的压力造成的.
- 当地冰的增长会导致邻近的水凝脱水.
- 低温吸附通过将水吸引到冰上来推动冰的生长,从而导致干燥引起的断裂.
结论:
- 水凝中结损伤的主要机制是通过冷引发的脱水诱导的骨折.
- 结损伤与干燥裂纹有很大的相似之处.
- 这些发现提供了对冷保存,食品科学和升现象的见解.
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