在HDPE和PP中模拟压力放松行为,使用分数导数
Karla L Segura-Méndez1, Jesús G Puente-Córdova1, Flor Y Rentería-Baltiérrez2
1Facultad de Ingeniería Mecánica y Eléctrica, Universidad Autónoma de Nuevo León, Av. Universidad s/n, Cd. Universitaria, San Nicolás de los Garza 66455, Mexico.
Polymers
|February 26, 2025
概括
这项研究使用分数衍生模型分析了高密度聚乙烯 (HDPE) 和聚烯 (PP) 的粘性弹性. 分数Voigt-Kelvin (FVKM) 模型最好地描述了HDPE,而Kohlrausch-Williams-Watts (KWW) 模型适合PP,优化了聚合物表征.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物物理 聚合物物理
- 类风病学 类风病学 类风病学
背景情况:
- 了解聚合物粘性弹性对于材料在苛刻应用中的性能至关重要.
- 压力放松实验提供了对分子移动性和物质随时间的反应的洞察.
- 经典,分数和可符合的衍生模型为描述粘弹性行为提供了不同的方法.
研究的目的:
- 评估用于分析HDPE和PP的分子流动性的经典,分数和符合性衍生物.
- 确定最准确的数学模型来表示这些聚合物的粘弹性反应.
- 利用统计方法和优化技术来准确地表征材料.
主要方法:
- 对HDPE和PP进行了各种应变水平的压力放松实验.
- 使用了统计评估指标,包括R2,AAD和MSE.
- 多变量变量分析 (MANOVA) 和响应表面方法 (RSM) 用于模型优化.
主要成果:
- 弹,分数麦克斯韦 (FMM),分数沃伊特-凯尔文 (FVKM) 和科尔劳什-威廉姆斯-瓦茨 (KWW) 模型在描述压力放松方面表现出有效性.
- RSM分析表明,模型选择对结果产生重大影响.
- 对于HDPE而言,FVKM模型是最佳的,而KWW模型则是最佳的.
结论:
- 选择适当的数学模型,以统计优化为指导,对于准确的聚合物粘性弹性表征至关重要.
- 对HDPE和PP进行量身定制的模型选择可以提高对长期机械行为的预测.
- 该框架支持改善聚合物加工,产品设计和工业应用中的可靠性.
更多相关视频
相关概念视频
Plastic Behavior
184
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...
184
Residual Stresses in Bending
147
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...
147
Members Made of Elastoplastic Material
93
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...
93
Plasticity
2.1K
Plasticity is the property where an object loses its elasticity and undergoes irreversible deformation, even after the deformation forces are eliminated. If a material deforms irreversibly without increasing stress or load, then this is called ideal plasticity. For example, when a force is applied to an aluminum rod, it changes its shape, but it does not return to its original shape once the force is removed. Plastic deformation or ductility is thus a permanent deformation or change in the...
2.1K
Plastic Deformations
79
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...
79
Residual Stresses
203
Residual stresses reside in a structure even after removing the original stress inducer. This phenomenon often arises from varied plastic deformations across different parts of a structure. Consider a rod stretched beyond its yield point. It will not regain its original length due to permanent deformation. Even after load removal, the rod does not entirely lose stress because of uneven plastic deformations, resulting in residual stresses. The computation of these stresses in structures is...
203


