Incremental Casting: The generativ droplet-based manufacturing of parts using aluminum alloys

点击翻译按钮获取中文摘要

Generative manufacturing methods have been growing constantly in the last 20 years. Today even metals like titan and aluminum can be processed using selective beam melting technologies. The downside of those technologies is the need for specials powders as base materials, which make the produced parts rather expensive. An alternative technology is the droplet-based manufacturing that processes liquid metal and therefore does not need an elaborate base material. The aim of this project is to create a printing system that can produce small droplets of aluminum alloy with a high frequency. A small droplet (ca. 200 µm) is necessary to produce geometrically precise parts. And a high frequency (100 Hz) is needed to do that in an acceptable time. Moreover the complex binding process of two subsequent droplets is examined. In this binding process a liquid droplet 2 hits an already (partly) solidified droplet 1. To enable good bonding between them, droplet 1 needs to partly melt and mix with droplet 2. That means, that geometry and bonding quality is influenced by the local thermal condition during the process. Which is why the bonding should be investigated in detail during this project. A particular focus lies on the influence of alloying elements. They not only control physical properties like surface tension, viscosity and heat convection but also influence the morphology of solidification. The arrangement, which is set up during this project, is going to be able to print parts with a maximum size of 50x50x50 mm³.