正规和不规则的毛孔分布对多孔材料弹性的影响:无微结构的有限元素研究
Prajjayini Chakma1, Yunhua Luo1
1Department of Mechanical Engineering, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
Materials (Basel, Switzerland)
|September 28, 2024
概括
多孔材料的刚度在很大程度上取决于孔隙的排列. 不规则的毛孔大大降低了度,而规则的毛孔保持了更长的时间,影响了分析模型的准确性.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 计算建模 计算建模
背景情况:
- 对于多孔材料的常规模型 模量往往缺乏微观结构细节.
- 预测有效的硬度需要了解孔隙分布如何影响机械性能.
研究的目的:
- 为了研究正规与不规则孔隙分布对多孔材料刚性的影响.
- 对实验数据进行无微结构有限元模型 (MF-FEM) 的验证.
- 评估基于孔隙结构的现有分析模型的准确性.
主要方法:
- 使用了无微结构的有限元模型 (MF-FEM).
- 为了确保模型可靠性,进行了趋同研究.
- 使用实验数据验证了MF-FEM结果.
主要成果:
- 不规则的毛孔微结构导致模量急剧下降,在~50%的毛孔度接近零.
- 正常的孔隙微结构表现出更渐进的刚度降低,保持显著的模量,高达~90%的孔隙度.
- 该研究确定了特定的分析模型,这些模型更适合定期或不规则的毛孔分布.
结论:
- 孔隙分布模式对于准确预测多孔材料的机械行为至关重要.
- MF-FEM提供了一种可靠的方法来分析微结构对材料刚性的影响.
- 现有的分析模型有局限性,取决于假设的孔隙结构,需要仔细选择准确的预测.
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