Simulative prediction of the manufacturing process in wire-arc additive manufacturing (WAAM) (T03#)

电弧增材制造 (WAAM) 制造过程的模拟预测 (T03

• 批准号: 470693600
• 金额: --
• 依托单位: Institut für Schweißtechnik und Fügetechnik (ISF)
• 依托单位国家: 德国
• 项目类别: Collaborative Research Centres (Transfer Project)
• 财政年份: 2022
• 资助国家: 德国
• 起止时间: 2021-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/470693600?language=en
• 关键词: Simulative; prediction; manufacturing; process; wire

Additive manufacturing holds enormous potential for the future development of the metal processing industry. In particular, the modification of low-cost semi-finished products by individualized structures expands the manufacturing possibilities and increases flexibility and cost-effectiveness in small series. In the field of welding technology research, the development of GMAW process variants for additive manufacturing is currently being increasingly considered (WAAM - wire arc additive manufacturing). This makes it possible to produce metallic components with different topologies directly from the molten metal. It implies that the topology of the substrate is determined during the process by the process itself. A key to the efficient development of an additive manufacturing chain is therefore the availability of mathematical models that enable digital precalculation of the necessary process steps. In particular, this requires a physics-based numerical model of the welding process used. Approaches to this already exist in the field of joint welding, but have not yet been transferred to the additive manufacturing of structures. This will be done in the proposed transfer project with a novel approach, which is expected to solve the numerical problem with reasonable computational effort in the future. In SFB1120, the relationship between molten pool flows during gas metal arc welding and the resulting weld geometry is being researched. So far, the hydrodynamic equations of the molten pool flows have mainly been solved using the Euler approach, where the computational mesh discretizes the entire space of the simulation domain. This approach is particularly well suited for the numerical study of the physical effects of conventional GMA welding, where a linear motion of the torch on a flat plate can be assumed. However, this approach encounters limitations with the dynamic growth of the component geometry, as is the case in the WAAM process. The level-set or VOF methods used in the Euler approach also require the discretization of the entire space, which results in inefficiencies in terms of computational effort, especially for complex component geometries, even when using adaptive meshing strategies. This is contrasted with the SPH approach (smoothed particle hydrodynamics), in which only the considered mass of the material is discretized rather than the entire space of the simulation domain. In order to verify the applicability of the SPH method to the simulation of the MSG welding process, a case study was initiated as an accompaning project within the SFB1120 to confirm transferability to the MSG process. The project described here enables the transfer of the methods, which have so far been used exclusively in the field of basic research, to the field of industrially relevant application-oriented models.

增材制造为金属加工行业的未来发展提供了巨大的潜力。特别是，通过个性化结构对低成本半成品进行修改，扩大了制造可能性，并提高了小批量生产的灵活性和成本效益。在焊接技术研究领域，目前越来越多地考虑用于增材制造的GMAW工艺变体的开发（WAAM -焊丝电弧增材制造）。这使得可以直接从熔融金属生产具有不同拓扑结构的金属部件。这意味着衬底的拓扑结构在工艺期间由工艺本身确定。因此，有效开发增材制造链的关键是数学模型的可用性，这些模型可以对必要的工艺步骤进行数字化预先计算。特别地，这需要所使用的焊接工艺的基于物理的数值模型。对此的方法已经存在于接头焊接领域中，但尚未转移到结构的增材制造中。这将在拟议的转移项目中使用一种新的方法来完成，预计该方法将在未来以合理的计算工作量解决数值问题。在SFB 1120中，正在研究熔化极气体保护焊过程中熔池流动与焊缝几何形状之间的关系。到目前为止，熔池流动的流体动力学方程主要使用欧拉方法求解，其中计算网格离散化模拟域的整个空间。这种方法特别适合于常规GMA焊接的物理效应的数值研究，其中可以假设焊炬在平板上的线性运动。然而，这种方法遇到的限制与组件的几何形状的动态增长，是在WAAM过程中的情况。欧拉方法中使用的水平集或VOF方法也需要对整个空间进行离散化，这导致计算工作量方面的效率低下，特别是对于复杂的组件几何形状，即使使用自适应网格化策略也是如此。这与SPH方法（平滑粒子流体动力学）形成对比，在SPH方法中，仅对所考虑的材料质量进行离散化，而不是对模拟域的整个空间进行离散化。为了验证SPH方法对MSG焊接过程模拟的适用性，在SFB 1120中启动了一个案例研究作为验证项目，以确认可转移到MSG过程。这里所描述的项目能够将迄今为止仅用于基础研究领域的方法转移到工业相关的应用型模型领域。