Mechanical properties of laser powder bed fusion produced overhang parts with different support geometries: an experimental study


Gülcan O., Günaydın K., Çelik A., YASA E.

Progress in Additive Manufacturing, cilt.9, sa.2, ss.211-229, 2024 (ESCI) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 9 Sayı: 2
  • Basım Tarihi: 2024
  • Doi Numarası: 10.1007/s40964-023-00443-6
  • Dergi Adı: Progress in Additive Manufacturing
  • Derginin Tarandığı İndeksler: Emerging Sources Citation Index (ESCI), Scopus
  • Sayfa Sayıları: ss.211-229
  • Anahtar Kelimeler: Laser powder bed fusion, Contactless support, Tooth support, Line support, Downskin surfaces, SURFACE-ROUGHNESS, FATIGUE PERFORMANCE, TITANIUM-ALLOYS, BEHAVIOR, SLM, OPTIMIZATION, DESIGN
  • Eskişehir Osmangazi Üniversitesi Adresli: Evet

Özet

Additive manufacturing technologies give engineers and researchers a high level of design freedom to produce complex components or entire assemblies previously impossible or impractical to manufacture by conventional means. Although additive manufacturing has many advantages compared to conventional machining, it has some drawbacks, two of which are higher surface roughness and dimensional inaccuracy of as-built part surfaces especially in overhang features. Support structures are one of the solutions to mitigate these drawbacks at a cost of additional post-processing efforts. The aim of the present study is to investigate the effect of different support geometries on the mechanical properties of laser powder bed fusion manufactured Inconel 718 overhang parts. The tested support geometries are comprised of several pieces to ease post-processing instead of using single-piece supports filling all over the overhang surface. One of the tested support structures is contactless support with no direct contact between the part and the support itself. The others are tooth support where the contact is on the tooth faces and line support where the contact is along a line. The thickness of each support piece and the spacing between the two support pieces were used as design variables. The dimensional accuracy of printed specimens with respect to the computer-aided geometry, distortion of overhang features, microhardness through the thickness, microstructural changes of overhang surface, and surface roughness of overhang features was experimentally evaluated. The results revealed that support type, support spacing and support thickness directly affect the performance characteristics used in this study.