Material- and process oriented non-destructive testing of additively manufactured components by computed tomography

通过计算机断层扫描对增材制造部件进行面向材料和工艺的无损检测

• 批准号: 398368987
• 负责人: Dr.-Ing. Stefan Dietrich
• 金额: --
• 依托单位: Institut für Angewandte Materialien - Werkstoffkunde (IAM-WK)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/398368987?language=en
• 关键词: Material; process; oriented; non; destructive

Selective laser melting (Abbr. SLM) is an additive manufacturing process (Abbr. AM), in which metallic structural components can be produced by the incremental application and melting of powder layers. The high geometric complexity of such components has led to the AM being investigated in many industrial fields in recent years and tested for their applicability. Within this rapid development of SLM, however, a large number of material-related questions and problems arise which are fundamental in the application and qualification of this new technology and the components produced with it. For example, a controllable and reproducible porosity, which is necessary for a safe use in structural components, cannot be guaranteed for most materials. At the same time, the anisotropy in the mechanical material behavior due to the directionally solidified microstructure is caused by the layerwise manufacturing process. Due to the inevitable occurrence of such characteristics and imperfections, the question of the material analysis and quality assurance of finished components and the correlation to the manufacturing parameters and component geometries is still at the beginning of research. Non-destructive testing represents an important step on the way to comprehensive microstructure analysis and component qualification.The aim of this project is therefore to investigate the relationships between microstructure and resulting mechanical properties to the process parameters and the component geometry based on X-ray microtomographic methods and thus to improve the process control with regard to the reduction and evolution of the porosity. For this purpose, the aluminium alloy AlSi10Mg, which is widely used in SLM, will be investigated under variation of laser speed, laser power and hatch spacing for various engineering geometries and build directions. This allows evaluation of process-structure-property. Within the scope of this task, automated, materialographic evaluation methods are to be developed mainly on the basis of X-ray microtomographic data for microstructural features in SLM. For the first time, this allows for a possible linking of the three-dimensionally visualized process parameters and the component shape with the microstructural characteristics and the mechanical component properties. This opens the way for a real process control and a prediction of the component behavior based on material modeling. On the basis of these extracted correlations in samples and component-like geometries, a validation of the modeling of mechanical properties in an in-situ test is carried out on a test geometry.

选择性激光熔化（Selective Laser Melting，缩写为SEL）SLM）是一种增材制造工艺（Abbr. AM），其中金属结构部件可以通过粉末层的增量施加和熔化来生产。这些部件的高度几何复杂性导致近年来在许多工业领域中研究AM并测试其适用性。然而，在SLM的快速发展过程中，出现了大量与材料相关的问题和难题，这些问题和难题对于这种新技术及其所生产的部件的应用和鉴定是至关重要的。例如，对于大多数材料来说，不能保证可控制和可再现的孔隙率，而这是安全使用结构部件所必需的。同时，由于定向凝固的微观结构，分层制造工艺导致了材料力学行为的各向异性。由于这些特性和缺陷的不可避免的出现，成品部件的材料分析和质量保证以及与制造参数和部件几何形状的相关性问题仍处于研究的初期。无损检测是实现全面微观结构分析和部件质量评定的重要一步，因此，本项目的目的是基于X射线显微层析成像方法，研究微观结构和机械性能与工艺参数和部件几何形状之间的关系，从而改善工艺控制，减少和改善孔隙率。为此，将针对各种工程几何形状和建造方向，研究激光速度、激光功率和舱口间距变化对空间光调制器中广泛使用的铝合金AlSi 10 Mg的影响。这允许评估过程-结构-性质。在这一任务的范围内，自动化，材相评价方法主要是开发的基础上的X射线显微断层扫描数据的微观结构特征的SLM。这是第一次允许三维可视化的工艺参数和部件形状与微观结构特征和机械部件性能的可能联系。这为真实的过程控制和基于材料建模的部件行为预测开辟了道路。在这些提取的相关性的基础上，在样品和组件样的几何形状，在原位测试中的力学性能的建模进行验证的测试几何形状。