Melt dynamics in remote laser material processing

远程激光材料加工中的熔体动力学

• 批准号: 407703212
• 负责人: Professor Dr.-Ing. Michael Schmidt
• 金额: --
• 依托单位: Lehrstuhl für Photonische Technologien (LPT)
• 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 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/407703212?language=en
• 关键词: Melt; dynamics; remote; laser; material

Remote Fusion Cutting (RFC) or Front Pressure Cutting has high potential for various industrial applications compared to conventional gas-assisted cutting processes due to its resource efficiency and its more flexible feasibility in industry. Stable process layout, however, is crucial to make use of this potential. Currently, the process behaves often instable regarding changes of parameters and the process understanding needed to explain or resolve this behavior is lacking.Therefore, in the proposed project the process understanding necessary for stable process layout will be developed. In order to understand the process comprehensively, not only the process of RFC, but also the borders of its process window, i. e. the transitions to the welding regime will be investigated. In the first step, the analysis algorithms necessary for the experiments and the already developed simulation model will be adapted to the process, improved and verified. Then, the process will be examined experimentally and simulatively to analyze and understand the mechanisms of material removal. More specifically, topology, shape and size of the interaction zone will be investigated videgraphically and simulatively and it will be clarified how these characteristics influence melt flow and material removal in RFC. Furthermore, it will be analyzed, primarily simulatively, how evaporation and the associated vapor pressure influence melt flow and how surface tension, vapor pressure and hydrodynamic pressure behave in RFC and in the transitions to welding. Since RFC reacts to changes of track geometries way more sensitively than welding and this often leads to loss of cut, it will be investigated videographically and simulatively how the track geometry influences the shape of the interaction zone, the melt flow and the material removal. Additionally, it will be investigated how and how much the laser power influences the maximum feed rate and the quality of the cut edges.Due to the verified fluiddynamic process model used in the project, in case of differences between experiment and simulation in certain areas of the process, the cause of the differences can be limited to an error in the implemented model or to false material properties. Therefore, by comparisons with experiments and iterative changes of the model process understanding can be built. This process understanding will be used to investigate possibilities to control and stabilize the process, e. g. by modulation of the laser power or modifications of the intensity distributions using phase masks. This knowledge will be condensed in user rules to contribute to the industrial applicability of RFC.

与传统的天然气辅助切割过程相比，由于其资源效率和行业中更灵活的可行性，远程融合切割（RFC）或前压力切割对各种工业应用的潜力很高。但是，稳定的过程布局对于利用这种潜力至关重要。当前，对于参数的变化以及解释或解决此行为所需的过程理解通常是不可能的。因此，在拟议的项目中，将开发稳定过程布局所需的过程理解。为了全面地理解过程，不仅是RFC的过程，而且还可以理解其过程窗口的边界。 e。将调查向焊接制度的过渡。在第一步中，实验所需的分析算法和已经开发的仿真模型将适应该过程，改进和验证。然后，将对过程进行实验和模拟检查，以分析和理解材料去除的机制。更具体地说，将对录像带和模拟进行研究的拓扑，形状和大小，并将澄清这些特性如何影响RFC中的熔体流量和材料去除。此外，将主要分析蒸发和相关的蒸气压力如何影响熔体流动以及表面张力，蒸气压力和流体动力压力在RFC和焊接过渡中如何表现。由于RFC对轨道几何形状的变化反应比焊接更敏感，这通常会导致切割的损失，因此将在摄像机和模拟上进行调查，轨道几何形状如何影响交互作用区域的形状，熔体流量和材料去除。此外，将研究激光功率如何以及如何影响最大进料速率和切割边缘的质量。在项目中使用的经过验证的流体动力过程模型，如果过程的某些过程中的某些区域之间存在差异，则差异的原因可能仅限于实施模型或虚假材料属性中的差异。因此，通过与实验和模型过程理解的迭代变化进行比较。这种过程的理解将用于调查控制和稳定过程的可能性。 g。通过调制激光功率或使用相掩码对强度分布的修改。这些知识将在用户规则中凝结，以促进RFC的工业适用性。