Improved process stability in three-dimensional paper forming due to numerical modeling of the material inhomogeneity

由于材料不均匀性的数值模拟，提高了三维纸张成型的工艺稳定性

• 批准号: 415796511
• 负责人: Professor Dr.-Ing. Peter Groche
• 金额: --
• 依托单位: Institut für Produktionstechnik und Umformmaschinen
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/415796511?language=en
• 关键词: Improved; process; stability; three; dimensional

The aim of the research project is to improve the design and control of paper forming processes by taking into account the existing material inhomogeneity. To this end, the influence of the locally different properties on the macroscopic mechanical behavior of the material is to be investigated and numerically modeled. The applicants of TU Dresden (VM/VT) and TU Darmstadt (PtU) are cooperating on this project. They benefit from the complementary expertise, whereby they have focused on conventional (VM/VT) and active media-based (PtU) paper forming processes, so far. The applicants' approaches to numerical process mapping are based on micromechanical models (VM/VT) and the transfer of established models of metal forming to paper forming (PtU). The state of the art provides inconsistent information on the influence of locally inhomogeneously distributed material properties, such as density, on global mechanical properties. The work in the proposed project is intended to clarify which fluctuations in material properties have a significant influence on macroscopic behavior. For this purpose, different measurement methods such as formation measurement, digital image correlation and thermography are planned. These are integrated into classical material characterization methods such as the tensile test to observe the local mechanical behavior. When impressing different load scenarios, elastic and plastic strain components can also be separated from each other.The numerical modeling and parameterization of inhomogeneous material properties at element level represents the second part of the research project. The previously determined data is used and a numerical model is developed in three levels. In addition to the part that overlays the globally determined characteristic values with an inhomogeneous distribution at element level, a model for modeling delamination and damage (crack start) is developed. The three model levels are validated by comparison with example tests such as the tensile test and the bulge test. Finally, the model is integrated into three-dimensional, complete forming simulations to investigate the influence of material and process parameters on the forming result. The complementary experiences of the applicants from the fields of paper forming are used here. This makes it possible to derive specifications for forming-compatible paper production, robust process design and process control. Within the scope of this project, the question is clarified which property fluctuations in the material are responsible for the dispersion of the macroscopic characteristic values. Based on these results, numerical methods help to develop design guidelines for semi-finished products and paper forming processes.

研究项目的目的是通过考虑现有材料不均匀性来改善纸张形成过程的设计和控制。为此，应研究和数值建模局部不同特性对材料宏观机械行为的影响。 Tu Dresden（VM/VT）和Tu Darmstadt（PTU）的申请人正在该项目合作。他们从互补的专业知识中受益，这些专业知识将重点放在传统（VM/VT）和基于媒体（PTU）的纸质纸张形成过程中。申请人的数值过程映射方法基于微力模型（VM/VT）以及已建立的金属形成模型的转移到纸张形成（PTU）。最新的状态提供了有关局部不合并的物质特性（例如密度）对全球机械性能的影响的不一致的信息。拟议项目中的工作旨在阐明材料特性中哪些波动对宏观行为有重大影响。为此，计划了不同的测量方法，例如形成测量，数字图像相关和热力计。这些被整合到经典的材料表征方法中，例如拉伸测试，以观察局部机械行为。当给不同的负载方案留下深刻印象时，弹性和塑性应变成分也可以彼此分开。元素水平不均匀材料特性的数值建模和参数化代表了研究项目的第二部分。使用先前确定的数据，并在三个级别中开发数值模型。除了在元素级别覆盖与不均匀分布的全球确定特征值的部分外，开发了建模分层和损坏的模型（裂纹开始）。通过与示例测试（例如拉伸测试和凸起测试）进行比较来验证这三个模型级别。最后，将模型集成到三维完整的成型模拟中，以研究材料和过程参数对成型结果的影响。这里使用了纸质形成领域的申请人的互补经历。这使得可以得出形成兼容纸张生产，强大的过程设计和过程控制的规格。在该项目的范围内，澄清了材料中哪些财产波动的原因是宏观特征值的分散。基于这些结果，数值方法有助于制定半整合产品和纸张形成过程的设计指南。