Modelling the deformation and failure of sheet metal in high-strain rate forming

对高应变率成形中金属板材的变形和失效进行建模

• 批准号: RGPIN-2017-05956
• 负责人: Green, Daniel
• 金额: $ 2.7万
• 依托单位: University of Windsor
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=711187
• 关键词: Modelling; deformation; failure; sheet; metal

The manufacture of lightweight and crash-resistant passenger vehicles increasingly requires the use of difficult-to-form sheet materials. Lightweight materials such as advanced high strength steels, aluminum and magnesium alloys inherently have limited formability when shaped using conventional forming processes. However, high-strain rate forming technologies, such as electromagnetic and electrohydraulic forming have been developed because under specific conditions, sheet materials can achieve at least 100% increase in formability. This enhanced formability offers significant weight reduction opportunities to automotive part designers. In order to optimize these high-strain rate metal forming processes and render them as cost-effective as possible for industrial implementation, it is necessary to be able to numerically predict their outcome with a high degree of confidence. The applicant's prior research focused on developing computer models that can simulate electrohydraulic forming operations. However, significant work is still required in order to improve the accuracy of the simulations. This research program aims to improve the existing simulation models in such a way as to more accurately predict the deformation behaviour and the onset of fracture of sheet materials deformed at high-strain rates. It is proposed to conduct a series of mechanical tests on sheet specimens across a range of strain rates from 0.001 to 1000 s-1. The use of high-speed, high-resolution digital cameras during testing will facilitate the acquisition of experimental data that gives insights into material behaviour and help to develop more accurate simulation models. One of the novelties of this work will be to determine the fracture limits of sheet materials at high strain rate. It is also proposed that specimens be observed at different magnifications under the microscope in order to determine their micro-mechanical deformation and damage behaviour up to the onset of fracture. Again, simulation models will be developed that are able to predict the onset of fracture based on observed micro-mechanisms of deformation and failure. This research program will provide advanced training for four highly qualified personnel (two Master's degree students and two PhD students) and will lead to the development of more accurate numerical tools for the simulation of high-strain rate sheet metal forming processes. These models will also be very useful in predicting the crashworthiness of vehicles. This will also help to accelerate the adoption of high-strain rate forming processes into industrial practice and increase the use of lightweight sheet materials in automobiles. Furthermore, as the trainees in this research program are hired by Canadian automotive manufacturers, the expertise they will develop will contribute toward maintaining Canada's competitive edge in advanced manufacturing.

制造轻量化和抗碰撞的乘用车越来越需要使用难以成形的板材。轻质材料，如先进的高强度钢、铝和镁合金，在使用传统成形工艺成形时，固有地具有有限的成形能力。然而，高应变速率成形技术，如电磁和电液压成形技术已经发展起来，因为在特定的条件下，板材的成形性可以达到至少100%的提高。这种增强的成形性为汽车零部件设计者提供了显著的重量减轻机会。 为了优化这些高应变速率金属成形工艺，并使其尽可能具有工业实施的成本效益，有必要能够高度自信地对其结果进行数值预测。申请人之前的研究重点是开发能够模拟电液成型操作的计算机模型。然而，为了提高模拟的准确性，仍然需要做大量的工作。 本研究计划旨在改进现有的模拟模型，以便更准确地预测在高应变率下变形的板材的变形行为和断裂起始。建议对板材试件进行一系列的力学试验，应变率范围从0.001到1000 S-1。在测试过程中使用高速、高分辨率的数码相机将有助于获取实验数据，从而深入了解材料的行为，并有助于开发更准确的模拟模型。这项工作的创新之一将是确定板材在高应变率下的断裂极限。 还建议在显微镜下以不同的放大倍数观察试件，以确定其直到断裂开始时的微观机械变形和损伤行为。同样，将开发能够基于所观察到的变形和破坏的微观机制来预测断裂开始的模拟模型。 这项研究计划将为四名高素质的人员(两名硕士和两名博士生)提供高级培训，并将导致开发更精确的数值工具，用于模拟高应变率板材成形过程。这些模型在预测车辆的耐撞性方面也将非常有用。这也将有助于加快将高应变率成形工艺应用于工业实践，并增加汽车中轻质板材的使用。此外，由于该研究项目的受训人员受雇于加拿大汽车制造商，他们将开发的专业知识将有助于保持加拿大在先进制造业方面的竞争优势。