• Nový, Zbyšek
• Li, Ying
• Salvetr, Pavel
• Wolf, Gerhard
• Šípová, Martina
• Rott, Matěj
• Džugan, Jan
• Koukolíková, Martina

Abstract

<jats:title>Abstract</jats:title><jats:p>This work deals with the fabrication of one low density steel by mixing AISI S2 tool steel and AlSi10Mg powders using powder-based directed energy deposition (P-DED) technique. Two approaches of mixing powders were compared-continuous mixing during the process (in-situ) and mixing the powder prior to the process (premixed). The P-DED sample was characterised by a variety of techniques such as optical microscopy, scanning electron microscopy, electron backscatter diffraction, X-ray diffraction, and hardness measurement. Our findings demonstrate the successful achievement of steel with a 8 wt. % AlSi10Mg addition when two dissimilar powders are premixed, resulting in approximately 12% reduction in the density of S2 steel. Optimizing the powder feed rate and the ratio of AlSi10Mg powder contribute to an improvement of printability, eliminating materials separation, leading to a homogenous deposited part. Compared to the in-situ mixing case, the premixed process within the current process window generates a more homogeneous microstructure consisting of three phases: Ferrite, Fe<jats:sub>3</jats:sub>Al and Fe<jats:sub>3</jats:sub>AlC carbide. Whereas, the in-situ sample exhibits only two phases Ferrite and Fe<jats:sub>3</jats:sub>Al. The hardness of the premixed sample is found to be slightly higher compared to the in-situ sample.</jats:p>

Topics

• Deposition
• density
• impedance spectroscopy
• microstructure
• phase
• scanning electron microscopy
• x-ray diffraction
• carbide
• hardness
• tool steel
• electron backscatter diffraction
• optical microscopy
• directed energy deposition