Comparative Study of Powder and Wire Feedstock DED-printed Inconel 625 and 718 Superalloys : Surface Metrology and Tribology
Garrote Junco, María del Carmen (2026)
2026
Master's Programme in Materials Science and Engineering
Tekniikan ja luonnontieteiden tiedekunta - Faculty of Engineering and Natural Sciences
Hyväksymispäivämäärä
2026-07-28
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:tuni-202607268482
https://urn.fi/URN:NBN:fi:tuni-202607268482
Tiivistelmä
Directed Energy Deposition (DED) has become an increasingly important additive manufacturing technology for the fabrication and repair of high-value components manufactured from nickelbased superalloys. Among these materials, Inconel 625 and Inconel 718 are employed in the aerospace sector because of their outstanding mechanical properties and excellent resistance to corrosion and elevated temperature. Despite their extended application, the effects of processing parameters and feedstock type on the resulting surface quality and tribological performance require further investigation.
This work evaluates the influence of feedstock material by comparing powder-fed and wire-fed DED processes for Inconel 625. Twenty-two Inconel 625 specimens were manufactured using Wire-DED, while eight specimens were produced by Powder-DED, including four Inconel 625 and four Inconel 718 samples. The manufacturing conditions covered different combinations of laser power and scanning speed while maintaining a constant energy density. In addition, the tribological and surface characteristics of Powder-DED Inconel 625 and Inconel 718 were compared.
Surface integrity was assessed through metrological analyses of waviness and roughness, with particular attention to the differences between wire and powder feedstocks. For Powder-DED specimens, the evolution of surface waviness throughout successive deposited layers was also examined. Tribological behaviour was investigated by means of wear tests performed on representative specimens produced under both high- and low-power processing conditions. Hardness measurements were carried out to establish relationships between processing parameters, material composition, and mechanical response. Finally, scanning electron microscopy (SEM) was employed to analyse the worn surfaces and identify the dominant wear mechanisms associated with each material and processing condition.
This work evaluates the influence of feedstock material by comparing powder-fed and wire-fed DED processes for Inconel 625. Twenty-two Inconel 625 specimens were manufactured using Wire-DED, while eight specimens were produced by Powder-DED, including four Inconel 625 and four Inconel 718 samples. The manufacturing conditions covered different combinations of laser power and scanning speed while maintaining a constant energy density. In addition, the tribological and surface characteristics of Powder-DED Inconel 625 and Inconel 718 were compared.
Surface integrity was assessed through metrological analyses of waviness and roughness, with particular attention to the differences between wire and powder feedstocks. For Powder-DED specimens, the evolution of surface waviness throughout successive deposited layers was also examined. Tribological behaviour was investigated by means of wear tests performed on representative specimens produced under both high- and low-power processing conditions. Hardness measurements were carried out to establish relationships between processing parameters, material composition, and mechanical response. Finally, scanning electron microscopy (SEM) was employed to analyse the worn surfaces and identify the dominant wear mechanisms associated with each material and processing condition.