The Additive Manufacturing (AM) technology laser based Direct Energy Deposition (L-DED) with blown powder has gained increasing attention for processing crack prone high temperature materials such as nickel based superalloys or intermetallics.

The possibility of coupling the deposition processes with inductive preheating of the substrate and the de-posited materials allows the tailoring of thermal boundary conditions to prevent hot as well as cold cracking phenomena. In addition, the simultaneous feeding of multiple powders into the process zone (in-situ alloy-ing) can be used for a rapid screening of different alloy compositions and their processability in a high throughput manner. Within this contribution the approach of combining DED with inductive preheating and in-situ alloying for investigating multiple compositions within system NiAl-Ta shall be presented.

Firstly, the alloys Ni50Al50 and Ni50Al42Ta8 were investigated regarding required process parameters and preheating temperatures to achieve a crack free processing, which was accomplished by applying preheat-ing temperatures of up to 1100 °C. The resulting microstructures were analyzed by light optical microscopy (LOM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), elec-tron backscattered diffraction (EBSD) as well as X-ray diffraction (XRD).

Secondly, by simultaneous processing of both materials and a layer wise adaption of the powder feeding rates a graded wall specimen exhibition a varying Ta content with increasing build height was fabricated. Due to the layer wise increasing amount of Ta the microstructure gradually changes from a single phase ß-NiAl to a C14 Laves-phase reinforced ß-NiAl structure. By increasing the Ta content from 1.47 at.-% to 8.02 at.-% an increase in C14 area fraction from 4.29 % to 19.78 % can be observed. Additional hardness HV 0.1 measurement along the build-up direction show an increase in hardness from 300 HV 0.1 up to 650 HV 0.1.