确定多孔材料的微观结构及其与有效机械性质的关系
Kangni Chen1, Hongling Qin2, Zhiying Ren1
1Department of Vehicle Engineering, Institute of Metal Rubber & Vibration Noise, Fuzhou University, Fuzhou, 350116, China.
Scientific reports
|October 23, 2023
概括
这项研究为储存液体的3D多孔材料提供了模型,揭示了多孔结构设计如何影响机械性能. 关键的发现表明,毛孔数量,生长随机性和大小随机性显著影响材料强度,毛孔分布不规则的影响最小.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 计算机建模 计算建模
背景情况:
- 了解微观结构和宏观机械性能之间的关系对于设计先进的多孔材料至关重要.
- 多孔液体储存介质需要精确控制其由其复杂的内部结构影响的机械行为.
研究的目的:
- 开发一种用于生成3D开放细胞多孔结构的方法,并预测它们的有效机械性质.
- 分析六个关键的微观结构设计参数对多孔材料机械行为的影响.
- 通过3D打印和压缩测试获得的实验数据来验证数值预测.
主要方法:
- 基于位移边界条件的均质化理论被用来预测有效的机械性质.
- 提出了一种新的方法,使用6个设计参数生成3D开放细胞多孔材料:孔数,多孔度,孔分布不规则性,孔生长随机性 (x,y) 和孔大小随机性.
- 创建和分析了约25%孔隙的代表体积元素 (RVE),并使用SLA 3D打印制造的标本进行实验验证.
主要成果:
- 数值结果表明,当RVE孔数达到9时,其可重复性很好.
- 最初孔隙分布的不规则性对RVE的有效机械性能产生了很小的影响.
- 毛孔生长和毛孔大小的随机性增加显著削弱了z方向的机械性质,同时减少了x和y方向的削弱.
结论:
- 该研究成功地确定了3D多孔材料的微观结构与它们的宏观机械性能之间的联系.
- 设计参数,特别是孔隙生长和尺寸随机性,严重影响机械性能,观察到显著的叠加效应.
- 这些发现为针对特定应用的多孔结构的定制设计提供了宝贵的见解,例如液体存储介质.
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