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.

该研究项目的目的是通过考虑现有材料的不均匀性来改进纸张成形过程的设计和控制。为此，局部不同的属性对材料的宏观力学行为的影响进行研究和数值模拟。德累斯顿工业大学（VM/VT）和达姆施塔特工业大学（PtU）的申请人正在合作进行该项目。他们受益于互补的专业知识，因此，他们一直专注于传统的（VM/VT）和主动媒体为基础的（PtU）纸张成型工艺，到目前为止。申请人的数值工艺映射方法是基于微机械模型（VM/VT）和将所建立的金属成形模型转移到纸成形（PtU）。现有技术提供了关于局部不均匀分布的材料特性（例如密度）对整体机械特性的影响的不一致信息。在拟议的项目中的工作是为了澄清材料性能的波动对宏观行为有显着的影响。为此，计划采用不同的测量方法，如地层测量、数字图像相关和热成像。这些都被集成到经典的材料表征方法，如拉伸试验，以观察局部的机械行为。当施加不同的载荷情况下，弹性和塑性应变分量也可以彼此分离。在单元级的非均匀材料属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，并在三个层次上开发了数值模型。除了覆盖的部分，全球确定的特征值在元素级的非均匀分布，模型分层和损伤（裂纹开始）的开发。通过与拉伸试验和胀形试验等实例试验的比较，验证了这三个模型水平。最后，将该模型集成到三维完整的成形模拟中，研究材料和工艺参数对成形结果的影响。这里使用了来自造纸领域的申请人的互补经验。这使得能够获得成形兼容纸张生产、稳健工艺设计和工艺控制的规格。在这个项目的范围内，澄清的问题，在材料中的属性波动是负责的宏观特征值的分散。基于这些结果，数值方法有助于开发半成品和纸张成型工艺的设计指南。