用有限元方法评估聚合物的机械性质的赫兹接触模型的分析
Laisvidas Striska1,2, Rokas Astrauskas3, Nikolajus Kozulinas3
1Department of Nanotechnology, Center for Physical Sciences and Technology, Sauletekio al. 3, 10257 Vilnius, Lithuania.
Polymers
|November 27, 2025
概括
原子力显微镜 (AFM) 可以不准确地测量材料的刚性. 这项研究揭示了赫兹模型高估了接触面积,导致低估了.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 机械工程 机械工程
背景情况:
- 原子力显微镜 (AFM) 是一种用于量化材料机械性质的标准技术,特别是模量.
- 实验室之间AFM结果的差异突出了方法论中尚未解决的问题.
- 常用于AFM数据分析的赫兹模型在准确确定接触参数方面存在局限性.
研究的目的:
- 为了调查赫兹模型在AFM内分析中的局限性.
- 通过AFM获得的扬斯模量测量的分歧的原因.
- 开发一种更准确的方法来确定尖端样本接触半径和模.
主要方法:
- 使用原子力显微镜 (AFM) 采用球形探针 (20纳米和2微米半径) 入聚乙烯 (PVC).
- 采用有限元分析 (FEA) 来建模尖端样本接触并确定准确的接触半径.
- 将AFM衍生的接触半径和模量与宏观测量进行比较 (ISO 527-1:2019).
主要成果:
- 与FEA相比,赫兹模型系统地高估了尖端样本接触半径.
- 与赫兹模型预测相比,FEA校正的接触半径比赫兹模型预测小15.46% (20纳米探针) 和小57.9% (2微米探针).
- 赫兹模型对接触面积的高估导致了对扬模量的低估.
结论:
- 赫兹模型在接触半径确定方面的局限性使得基于AFM的模量测量产生了显著的偏差.
- 准确的接触半径测定对于使用AFM可靠的机械性能量化至关重要.
- FEA提供了一种更准确的方法来建模AFM接触力学,改进了Young的模量测量.
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