在拉伸变形过程中与光学参数相关的高密度聚乙烯样品晶度变化的多模无损现场观测
Karoline Felbermayer1, Sandrine van Frank1, Bettina Heise1
1RECENDT-Research Center for Non Destructive Testing GmbH, Science Park 2, 2.OG, Altenbergerstrasse 69, 4040 Linz, Austria.
Sensors (Basel, Switzerland)
|October 16, 2024
概括
这项研究结合了太赫兹 (THz) 光谱,光学连贯性断层扫描 (OCT),红外 (IR) 和拉曼光谱,在拉伸测试期间分析高密度聚乙烯 (HDPE). 多模式方法将光学参数与材料晶度变化相关联.
科学领域:
- 材料科学 材料科学 材料科学
- 光学是什么?光学是什么?光学是什么?
- 频谱学是一种光谱学.
背景情况:
- 非破坏性光学测试方法对于材料研究至关重要,提供各种材料参数信息.
- RECENDT开发了一种多模式的实验设置,集成了太赫兹 (THz) 光谱,光学连贯性断层扫描 (OCT),红外 (IR) 和拉曼光谱.
- 这种设置与拉伸试验阶段相结合,用于现场材料分析.
研究的目的:
- 在拉伸性测试期间收集高密度聚乙烯 (HDPE) 的材料信息,特别是晶度和光学参数.
- 为了比较常见的IR和拉曼光谱法与不太常见的THz和OCT方法的有效性.
- 为了确定光学参数和材料晶度变化之间的相关性.
主要方法:
- 使用了多模式实验设置,结合了THz光谱,OCT,IR光谱和拉曼光谱.
- 在具有不同晶度的HDPE样品上进行了拉力测试.
- 分析了光学参数,包括折射率,双折射率,散射衰变系数和透深度.
主要成果:
- 不同的光学方法 (THz,OCT,IR,Raman) 之间由于其独特的频率范围和测量方法而证明了互补性.
- 在拉力测试期间,成功地将确定的光学参数与观察到的HDPE晶度变化相关联.
- 展示了各种光学方法的相互联系及其衍生材料参数.
结论:
- 多模式光学设置有效地表征材料特性,如晶度和机械应力期间的光学参数.
- 未来的优化可以观察复合材料中的纤维对齐和聚合物中的应力分布.
- 这项研究为先进的聚合物表征开辟了道路,包括质量控制和材料测试.
相关概念视频
Plastic Behavior
190
A material's elastic behavior is characterized by the disappearance of stress once the load is removed, allowing the material to return to its original state. However, when stress surpasses the yield point, yielding commences, marking the onset of plastic deformation or permanent set. This change from elastic to plastic behavior is influenced by the peak stress value and the duration before the load is removed. An intriguing observation occurs when a specimen is loaded, unloaded, and...
190
Plastic Deformations
84
It is essential to understand how structural members behave under plastic deformation when the bending stress exceeds the material's yield strength. This state of deformation permanently alters the shape of the member, in contrast to the linear elastic behavior observed before yielding. The strain at any point in the member is expressed in terms of maximum strain. Notably, the neutral axis, which coincides with the centroid during elastic bending, shifts away from the centroid under plastic...
84
Stress-Strain Diagram - Ductile Materials
643
The stress-strain relationship in ductile materials such as structural steel or aluminium is intricate and progresses through several stages. When a specimen is loaded, it initially exhibits a linear length increase, depicted by a steep straight line on the stress-strain diagram. It indicates the material is elastically deforming and will return to its original shape once unloaded. However, when a critical stress value is reached, plastic deformation begins. This stage sees substantial...
643
Strain-Energy Density
376
Understanding the strain energy density in materials under axial load is crucial for evaluating their mechanical behavior and durability. When a rod is subjected to such a load, it elongates and stores energy, known as strain energy, as potential energy within the material. This energy is measured in terms of energy per unit volume.
In the elastic region of a material, the relationship between the stress and the strain is linear and follows Hooke's Law. The strain energy density in this...
In the elastic region of a material, the relationship between the stress and the strain is linear and follows Hooke's Law. The strain energy density in this...
376
Polymer Classification: Crystallinity
2.8K
Unlike ionic or small covalent molecules, polymers do not form crystalline solids due to the diffusion limitations of their long-chain structures. However, polymers contain microscopic crystalline domains separated by amorphous domains.
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
2.8K
Members Made of Elastoplastic Material
94
The behavior of elastoplastic materials under bending stresses, particularly in structural members with rectangular cross-sections, is crucial for predicting material responses and understanding failure modes. Initially, when a bending moment is applied, the stress distribution across the section follows Hooke's Law and is linear and elastic. This distribution means the stress increases from the neutral axis to the maximum at the outer fibers, up to the elastic limit.
As the bending moment...
As the bending moment...
94


