Moisture is often claimed to be one of the main reasons for poor processability of powders when using L‑PBF processes. To determine the influence of moisture on the processability, gas atomized superalloy powder IN718 has been printed in two parallel runs: once in the as-received and dry condition and once after four weeks of storage in an atmosphere containing a relative humidity of 75%. Thereby different specimens have been prepared for notched impact tests, tensile tests, roughness, and metallographic analysis. Furthermore, the chemical composition of the powder before and after the build job as well as that of the printed parts have been analysed. The results obtained with the differently conditioned powders have been compared in the end to determine the influence of humidity on the processability on IN718 powder.
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