对注射成型聚合物材料的无otropic产量标准的简化表征
Sharlin Shahid1, Eskil Andreasson2, Viktor Petersson2
1Department of Mechanical Engineering, Blekinge Institute of Technology, 371 79 Karlskrona, Sweden.
Polymers
|January 17, 2024
概括
精确的注射成型聚乙烯的有限元素建模需要异型性产量标准. 该研究表明,巴拉特Yld91和巴拉特Yld2004-18P标准,通过简单的拉伸试验校准,有效捕获材料异性质.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 计算力学 计算力学 计算力学
背景情况:
- 注射成型聚乙烯由于加工诱导的聚合物链方向而表现出显著的异型机械行为.
- 类似于·米塞斯的同otropic yield标准通常用于有限元素建模 (FEM) 为了简单性,但为了异otropic 材料而牺牲准确性.
- 对聚乙烯组件的准确建模需要先进的构成模型,这些模型可以考虑材料的异构性.
研究的目的:
- 为了评估低密度聚乙烯 (LDPE) 的FEM的异构性产量标准 (Hill 1948,Barlat Yld91,Barlat Yld2004-18P) 的准确性和计算效率.
- 为了研究一种简化的校准技术,仅使用单轴拉伸试验和数字图像相关性 (DIC) 来确定异型性产量标准.
- 为了比较这些异轴性标准的性能与异轴性·米塞斯标准在大单轴拉伸变形下.
主要方法:
- 使用有限元建模 (FEM) 来模拟LDPE的机械行为.
- 研究了三种异型产量标准 (Hill 1948,Barlat Yld91,Barlat Yld2004-18P),并与·米塞斯标准进行了比较.
- 使用单轴拉伸试验和DIC的简化校准方法被开发和应用,以确定构成参数.
主要成果:
- 与·米塞斯标准相比,非同位性产量标准,特别是巴拉特Yld91和巴拉特Yld2004-18P,在预测LDPE的变形-应力-应变行为方面提供了更好的准确性.
- 使用单轴拉伸试验和DIC的简化校准技术在Barlat组收益率标准上被证明有效.
- 虽然所有研究的异构性标准都捕捉到了一定程度的异构性,但Barlat Yld91和Barlat Yld2004-18P在不同的精度水平上表现出更高的保真度.
结论:
- 对注射成型聚乙烯的精确FEM来说,异型产量标准是必不可少的.
- 巴拉特Yld91和巴拉特Yld2004-18P标准可以有效地使用最小的一组单轴拉伸试验进行校准.
- 简化校准方法增强了工程模拟中先进的异构型模型的实际应用.
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