平面,纹或纹:弹性薄膜在经历连续压缩的粘性基板上放松
Xianheng Guan1, Nhung Nguyen2, Luka Pocivavsek2
1Department of Mechanical Engineering and Material Science, University of Pittsburgh, Pittsburgh PA 15238, United States.
概括
一项计算研究揭示了薄的弹性薄膜如何在粘性基板上曲. 较短的薄膜保持平坦,而较长的薄膜由于压缩动力学而产生纹,然后局部化的脊柱.
科学领域:
- 材料科学 材料科学 材料科学
- 固体力学 固体力学是什么
- 流体动力学 流体动力学
背景情况:
- 基板上的薄弹性薄膜在各种应用中至关重要.
- 了解压缩下的薄膜行为对于材料设计至关重要.
- 粘性基板与弹性基板相比,具有独特的能量消散动态.
研究的目的:
- 在压缩下对粘性基板上的薄弹性薄膜的曲动力学进行计算研究.
- 根据薄膜的长度和应变,识别不同的变形状态 (平坦,纹,纹).
- 分析粘性基板在调节能量消散机制中的作用.
主要方法:
- 使用有限元计算建模.
- 模拟分析了与粘性基板结合的薄弹性薄膜的动态.
- 这项研究探讨了压缩速率,薄膜长度和应变的影响.
主要成果:
- 由于快速的结束放松,短片保持平坦.
- 较长的薄膜曲,最初形成纹包,进而演变成局部的脊柱.
- 构建了一个州地图,划分了平面,纹和纹的薄膜配置的区域.
- 脊局部化是由于较低的能量状态和较快的纹发展之间的平衡造成的.
结论:
- 粘性基板控制弹性能量的消散,影响曲模式.
- 薄膜的长度和施加的应变是决定曲形态的关键参数.
- 从纹过渡到局部脊是由竞争的能量和动力因素驱动的.
相关概念视频
Residual Stresses in Bending
155
In the study of elastoplastic members subjected to bending moments, understanding the loading and unloading phases is crucial for assessing material behavior and structural integrity. During the loading phase, as the bending moment increases, the material initially responds elastically, adhering to Hooke's Law, where stress is directly proportional to strain. When the load exceeds the yield strength, plastic deformation occurs, resulting in permanent strain and deformation that remains even...
155
Plastic Behavior
195
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...
195
Elastic Strain Energy for Shearing Stresses
180
As discussed in previous lessons, strain energy in a material is the energy stored when it is elastically deformed, a concept crucial in materials science and mechanical engineering. This energy results from the internal work done against the cohesive forces within the material. When a material undergoes shearing stress and corresponding shearing strain, the strain energy density, which is the energy stored per unit volume, is calculated. Within the elastic limit, where the stress is...
180
Relation between Poisson's ratio, Modulus of Elasticity and Modulus of Rigidity
260
Deformation occurs in axial and transverse directions when an axial load is applied to a slender bar. This deformation impacts the cubic element within the bar, transforming it into either a rectangular parallelepiped or a rhombus, contingent on its orientation. This transformation process induces shearing strain. Axial loading elicits both shearing and normal strains. Applying an axial load instigates equal normal and shearing stresses on elements oriented at a 45° angle to the load axis.
260
Elastic Strain Energy for Normal Stresses
148
Strain energy quantifies the energy stored within a material due to deformation under loading conditions, a fundamental concept in materials science and engineering. The strain energy can be modeled when a material is subjected to axial loading with uniformly distributed stress. In this scenario, the stress experienced by the material is the internal force divided by the cross-sectional area, and the strain induced is directly proportional to this stress through the modulus of elasticity.
If...
If...
148
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


