EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

The range of materials used for additively manufactured products is currently still very limited, as the materials often cannot be transferred to this new production technology or cannot compete with conventionally manufactured products in terms of properties. On the other hand, however, additive manufacturing such as laser powder-bed fusion (LPBF) offers completely new degrees of freedom for the development of novel alloys whose material properties lie far beyond those of conventionally manufactured products. In terms of this, each new alloy composition requires holistic development that consideres the entire process chain - from powder production to the additively manufactured and heat-treated component. The properties of the newly developed alloy can be adjusted either by in-situ heat treatment during LPBF or by a subsequent so called direct aging and can be varied over a wide range. In addition, the potential of specific in-situ technologies enabling a local modification of the microstructure will be discussed as promising methods further improvements of the overall properties.
The presented contribution focuses on selected developments along the process chain, which essentially support the realization of novel alloys with advanced properties.
Due to the high solidification rates of the melt pool in the LPBF process, extreme non-equilibrium states such as highly supersaturated solid solutions can be achieved, which allow exceptional properties. Using the example of the newly developed alloy Custalloy®, which is based on the cost-effective Al-Mg-Si system and, thus, suitable for automotive applications, it can be shown that strength and ductility values can be achieved, which are above of conventional high-strength 7xxx aerospace wrought alloys and close to the most performing, but highly cost and ressource intensive AM Alloy Scalmalloy®. As an outlook, locally acting in-situ technologies are shown, which allow promising local modification of the microstructure.