Micro-structuring and macro-structuring of deep drawing tools for dry forming condition

干成形条件下拉深工具的微观结构和宏观结构

基本信息

批准号：
244947573
负责人：
Professor Dr.-Ing. Eckhard Beyer
金额：
--
依托单位：
Professur für Formgebende Fertigungsverfahren
依托单位国家：
德国
项目类别：
Priority Programmes
财政年份：
2013
资助国家：
德国
起止时间：
2012-12-31 至 2019-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/244947573?language=en
关键词：
Micro structuring macro deep drawing

项目摘要

Large friction forces in forming processes reduce the process limits. Generally, lubricants are therefore used to reduce friction and enlarge the process window. However, the technological advantages of lubricants are accompanied by negative economic and ecological effects. Therefore, the elimination of lubricants from deep drawing processes by means of an integrated concept of a protective coating and micro- and macro structuring of the tool is studied and analysed during this project. Within the first phase, the different technologies of the integrative approach were fundamentally analysed and the deep-drawing process with tool structuring was experimentally verified. The general feasibility was demonstrated for axially symmetric parts. In the second funding period, the process principle has been further improved. For a time efficient process design an analytical model has been developed describing the influence of input parameters on the risk of wrinkling and bottom cracks. Furthermore, a feasibility study regarding high-strength steels indicated additional advantages of a macro-structured deep drawing process over standard processes. The reduction of friction forces was pursued by investigating coating technology and micro-structuring of tools and the wear behaviour of coated and structured surfaces and the interaction with blank and tool surface were investigated. All technologies were transferred to the design of a modular tool for non axially symmetric parts. Based on these results, the third research phase has the goal to implement an industrially relevant lubricant free deep drawing process for complex parts and high strength materials. The main approach remains an integrative application of different processes in the areas of macro-structuring, coating and micro-structuring. The enhancement of the macro-structuring into three-dimensional geometries is a key factor, because it allows the direct control of the material flow in tangential and radial direction, and therefore the systematic adjustment of stresses as well as bending and unbending to specifically set part characteristics. An adjusted semi-analytical model is used for designing the macro-structures and choosing process parameters. The corresponding high requirements of the forming process regarding friction and wear of the tools will be addressed with a combined approach of coating and micro-structuring. The goal is to improve on previous results by adjusting the coating and structuring processes. Specifically, a new coating with a fluor modified ta-C layer will be implemented and the chromium bonding layer will be substituted by a nitration process. Additionally, the DLIP process will adjusted by shortening pulse times and homogenising the laser beam in order to improve the quality of the micro-structure while minimising negative effects on the substrate. All technologies will be integrated and verified using the modular deep drawing tool from the second funding phase.

形成过程中的大摩擦力减少了过程限制。通常，润滑剂用于减少摩擦并扩大过程窗口。但是，润滑剂的技术优势伴随着负面的经济和生态影响。因此，在此项目中研究和分析了该工具的保护性涂层以及微观和宏结构的综合概念，从深度绘图过程中消除了润滑剂。在第一阶段，对整合方法的不同技术进行了根本分析，并通过实验验证了使用工具结构的深度绘制过程。证明了轴向对称零件的一般可行性。在第二个融资期间，该过程原则得到了进一步改善。对于时间效率的过程设计，已经开发了分析模型，描述了输入参数对皱纹和底部裂纹风险的影响。此外，一项关于高强度钢的可行性研究表明，宏观结构的深度绘图过程比标准过程的其他优势。通过研究涂料技术和工具的微观结构以及涂层和结构化表面的磨损行为，并研究了与空白和工具表面的相互作用，从而追求摩擦力的减少。将所有技术都转移到用于非轴向对称零件的模块化工具的设计中。基于这些结果，第三研究阶段的目标是为复杂的零件和高强度材料实施与工业相关的无润滑剂深度绘图过程。主要方法仍然是不同过程在宏观结构，涂料和微型结构领域的综合应用。将宏观结构增强为三维几何形状是一个关键因素，因为它可以直接控制切向和径向方向上的材料流，因此可以系统地调整应力以及弯曲和不弯曲以特定设置零件特征。调整后的半分析模型用于设计宏观结构和选择过程参数。形成过程对工具的相应高要求将通过涂层和微型结构的组合方法来解决。目的是通过调整涂料和结构过程来改善先前的结果。具体而言，将实现具有荧光修饰的TA-C层的新涂层，并将通过硝化过程代替铬粘结层。此外，DLIP过程将通过缩短脉冲时间和均质激光束来调整，以提高微结构的质量，同时最大程度地减少对底物的负面影响。所有技术将使用第二融资阶段的模块化深色绘图工具进行集成和验证。