使用激光振动计对受约束的凝中干燥引起的模块变化和内部应力进行表征
Karthik Yerrapragada1, Haocheng Yang1, Wonhyeok Lee1
1Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, 53706, WI, USA. eriten@wisc.edu.
Soft matter
|January 3, 2024
概括
这项研究使用模态分析来追踪在干燥过程中凝水凝机械性能的变化. 振动技术显示,随着水含量减少,弹性模块和内部应力不断演变.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 机械工程 机械工程
背景情况:
- 水凝是水膨胀的聚合物网络,用于各种应用.
- 水凝的特性随着含水量而变化,受外部刺激的影响.
- 胀或脱水会导致机械性能变化和内部应力.
研究的目的:
- 为了研究脱水引起的水凝机械性质的变化.
- 在干燥过程中量化弹性模块和内部应力的演变.
- 评估基于振动的技术对水凝的特征的有用性.
主要方法:
- 用于干燥凝水凝盘的模态分析.
- 无接触激光振动计测量自然频率和减噪比.
- 与预应力厚板模型进行比较,用于数据解释.
主要成果:
- 弹性模块和内部应力发现的水损耗高达80%.
- 凝的宽带损耗能力是从缓冲比率来确定的.
- 短暂的机械反应凸显了快速表征的需要.
结论:
- 模态分析有效地描述了水凝中脱水引起的机械变化.
- 基于振动和波动的技术为水凝特性提供了有前途的非接触方法.
- 了解这些变化对于各种行业的水凝应用至关重要.
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