编织涂层薄膜在循环拉伸过程中的复杂变形的建模分析
Li Cai1, Zhengyan Zhang2, Deng'an Cai1
1State Key Laboratory of Mechanics and Control for Aerospace Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
Polymers
|June 27, 2024
概括
这项研究增强了编织聚乙烯 (PVC) 涂层薄膜的构成模型,改善了离轴循环绘图的预测. 新的1D和2D模型在各种条件下准确地捕捉复杂的机械变形.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 聚合物科学 聚合物科学
背景情况:
- 现有的汉堡模型很难准确地表示编织涂层的离轴循环绘图.
- 了解制聚乙烯 (PVC) 涂层薄膜的机械变形对于材料的表征至关重要.
- 涂层薄膜中的循环变形过程需要复杂的建模方法.
研究的目的:
- 为了研究和建模PVC涂层薄膜在离轴循环绘制过程中的机械变形.
- 开发改进的一维 (1D) 和二维 (2D) 构成模型,以准确预测循环非线性变形.
- 为了验证拟议的模型与张力剪切合状态的实验数据进行验证.
主要方法:
- 开发一个改进的1D Burgers模型,考虑时间依赖的粘度和弹性-粘性变形比.
- 使用多项式函数构建一个2D非线性正方形模型.
- 实现一个反向算法与一个单一目标的遗传算法来确定剪切参数,规避剪切测试.
- 开发UMAT子程序用于轴外拉伸和循环拉伸模拟.
主要成果:
- 改进的1D模型在预测不同温度和负载率的周期性非线性变形方面显示出更高的准确性.
- 使用反向算法的2D模型有效地确定剪切多项式系数和模量,而无需直接剪切测试.
- 来自2D模型的模拟结果与实验性离轴循环拉伸试验数据密切匹配.
结论:
- 开发的1D和2D构成模型提供了编织PVC涂层薄膜变形的准确特征.
- 建议的智能反向算法方法在复杂材料建模中的参数识别中是有效的.
- 经过验证的2D模型准确地分析了在张力剪切合状态下编织的PVC涂层薄膜.
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