“Incremental Casting”: Support Material and Close-Loop Control of Layer Height for Direct Metal Printing with Aluminium

作为前一个项目的一部分，首次可以生产用于液滴基金属添加剂制造的水溶盐支撑结构。此外，高度传感器的实现以及与打印参数的耦合为几何误差补偿奠定了基础。支撑结构最初是整体式的。然而，由于盐类的导热系数低、凝固收缩大，盐类支撑结构的高度受到限制。只使用盐作为薄的释放层，可以最大限度地减少盐的热物理性质对工艺的影响。在本项目中，将开发一种制造释放支撑结构的工艺，并对其进行热模拟和表征。不同液滴大小的产生允许在组件内有针对性地改变液滴大小。这样，既可以更好地再现几何细节，也可以优化打印速度。为了研究这种方法，将开发G代码生成策略，并将表征合适的测试样本。

As part of the previous project, water-soluble salt support structures for the droplet-based additive manufacturing of metals could be produced for the first time. In addition, the implementation of a height sensor and coupling with the printing parameters created the basis for geometry deviation compensation. The support structures were initially monolithic. However, due to the low thermal conductivity and high solidification shrinkage of salts, the height of salt support structures is limited. The use of salts only as a thin release layer minimizes the influence of the thermophysical properties of the salt on the process. In this project continuation, a process for the fabrication of the release support structures will be developed, thermally simulated and characterized. The generation of different droplet sizes allows the targeted variation of the droplet size within a component. In this way, either geometric details can be better reproduced or the printing speed can be optimized. To investigate this approach, strategies for G-code generation will be developed and suitable test specimens will be characterized.