Characterization of the suitability of high manganese steels for the production of small sheet metal parts by multi-stage deep drawing

高锰钢多级拉深生产小型钣金零件的适用性表征

• 批准号: 423190740
• 负责人: Professor Dr.-Ing. Gerhard Hirt
• 金额: --
• 依托单位: Institut für Bildsame Formgebung (IBF)
• 依托单位国家: 德国
• 项目类别: Research Grants (Transfer Project)
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/423190740?language=en
• 关键词: Characterization; suitability; manganese; steels; production

In the automotive industry, relatively small, sometimes complicated and tube-shaped components with paramagnetic properties are required. They are used as components for valve drives or injection nozzles and are produced in multi-stage combined deep drawing and ironing drawing processes, e.g. by the Hubert Stüken GmbH. The currently used chromium-nickel steels show low strengths and a weak austenite stability. Hence, a replacement by austenitic high manganese steels (HMnS) is aimed. Preliminary tests of the application partner with a commercially available HMnS with a composition comparable to alloys investigated in the SFB 761 part project B2 have shown fundamental potential in terms of formability and increasing strength. Nevertheless, an unfavorable change of the microstructure during the multi-stage deep drawing process occurs due to twinning and martensite formation, which affects the mechanical and magnetic properties of the components. In the automotive industry, for example, common limit values of 2 - 5 A/cm must be kept for the magnetic properties. Already established methods for the design of deep-drawing processes cannot predict the change of the magnetic properties by martensitic transformation during multi-stage deep-drawing. The working hypothesis of this project is, that the formation of martensite is favored by very large deformations of φ>5 and/or multi-axial stress states occurring in the deep-drawing processes. The aim is therefore to systematically investigate the microstructure changes under these complex loads and to develop empirical models specifically in order to design process sequences targeting the final microstructure. For this, it is necessary to understand the underlying mechanisms under different multi-axial stresses and for different deformation states. Only the cooperation with the application partner enables an adequate definition of the requirements regarding the process-dependent material behavior and component properties. Based on this, a characterization method is to be developed which emulates the microstructure development occurring during multi-stage deep-drawing processes. On the basis of this basic experiment, an empirical model for the microstructure development in multi-stage deep drawing processes will be developed and validated. This model will then be used to design a suitable process sequence, e.g. for components without martensitic transformation, which will finally be produced experimentally at the industrial facilities of the application partner. The basic experiment developed in this project can help to validate material models for high strains with regard to future questions and thus contribute to the improvement of the simulative process design.

在汽车行业中，需要相对较小的，有时是复杂的管状组件，具有顺磁性。它们被用作阀门驱动器或注入喷嘴的组件，并以多阶段的深层绘图和熨烫绘图过程（例如由HubertStükenGmbH。当前使用的铬镍钢表现出低强度和弱的奥氏体稳定性。因此，瞄准了奥氏体高锰钢（HMN）的替代品。应用合作伙伴的初步测试，具有与SFB 761 Part项目B2中研究的合金相当的成分的市售HMN的初步测试，在可调性和增强强度方面表明了基本潜力。然而，在多阶段的深度绘图过程中，微观结构的不利变化是由于双胞胎和马氏体形成而发生的，这会影响组件的机械和磁性。例如，在汽车行业中，必须保留2-5个A/cm的公共极限值。已经建立的用于设计深绘图过程的方法无法预测多阶段深度绘制过程中马氏体变换的磁性变化。该项目的工作假设是，马氏体的形成受到φ> 5和/或在深度绘制过程中发生的多轴应力状态的非常大的变形所青睐。因此，目的是系统地研究这些复杂负载下的微观结构变化，并专门开发经验模型，以设计针对最终微观结构的过程序列。为此，有必要了解不同多轴应力和不同变形状态下的基本机制。只有与应用程序合作伙伴的合作才能适当地定义有关过程相关的材料行为和组件属性的要求。基于此，将开发一种表征方法，以模拟多阶段深度绘制过程中发生的微观结构发展。基于这个基本实验，将开发和验证多阶段深度绘图过程中微观结构开发的经验模型。然后，该模型将用于设计合适的过程序列，例如对于没有马氏体转换的组件，最终将在应用程序合作伙伴的工业设施实验生产。该项目中开发的基本实验可以帮助验证未来问题的高应变材料模型，从而有助于改善模拟过程设计。