Speaker
Description
As Additive Manufacturing (AM) technologies mature, the lack of tailored alloys becomes more and more of an obstacle for a widespread application for AM. Alloy development has historically been a costly process taking decades or centuries. In the case of AM, however, new improved alloys have to be developed much faster, calling for time- and resource-efficient alloy development methods. These methods have to fulfill two essential criteria: firstly, in situ alloy mixing must take place locally. Secondly, the cooling rates must be controllable in a wide range in order to match different AM processes ensuring matching microstructures and mechanical properties.
The newly developed Extreme High Speed Laser Material Deposition (EHLA) process meets these two criteria. However, the correlations between its numerous process parameters, resulting cooling rate and microstructure are not yet understood. In this paper, the influence of parameters such as laser power, process speed and powder mass flow on resulting cooling rate and microstructure of 316L is studied using metallographic methods and Scanning Electron Microscopy (SEM). Process parameters with a significant influence on cooling rate and microstructure will be determined, taking one of the first steps for alloy development guidelines for AM.