| About this Abstract |
| Meeting |
2024 AWS Professional Program
|
| Symposium
|
2024 AWS Professional Program
|
| Presentation Title |
Influence of Lack of Fusion Defects on Tensile Properties of Gas Metal Arc Directed Energy Deposition 316L and 316LSi |
| Author(s) |
Dominic Piccone, Luc Hagen, Stephan Tate, Jonah Klemm-Toole |
| On-Site Speaker (Planned) |
Dominic Piccone |
| Abstract Scope |
Gas metal arc-directed energy deposition (GMA-DED) is a high deposition rate additive manufacturing process that is ideal to produce large new and replacement parts that would typically be manufactured through forging or casting. One of the more common processing related defects in GMA-DED is lack of fusion (LOF) porosity. Understanding the conditions under which LOF forms and the resulting mechanical properties is crucial for enabling GMA-DED for structural components. In this work, 316L and 316LSi feedstocks were used to fabricate GMA-DED block-shaped builds with increasing hatch spacing, with the goal of determining when LOF forms. An infrared thermal camera was used during the build process to determine if LOF formation could be detected during the process. Room temperature tensile testing with specimens oriented parallel and perpendicular to the build direction was employed to evaluate the effects of these defects on tensile properties. It was found that with increasing hatch spacing, an increasing amount of LOF defects were observed between deposition passes using the in-process infrared camera. However, very few LOF pores were observed using optical microscopy of sections taken from the builds. Dye penetrant inspection of several cross sections from each build was needed to locate LOF pores. When defects were found, generally larger sizes were observed with larger hatch spacings. The increasing size and frequency of LOF pores from larger hatch spacings led to decreasing ultimate tensile strengths and total elongations in 316L, but no statistically significant effect on tensile properties was observed with 316LSi builds. Based on these results, the tensile properties of GMA-DED builds using 316LSi appear to be less sensitive to variations in hatch spacing and resulting LOF defects indicating this feedstock should be further investigated for structural applications. |
| Proceedings Inclusion? |
Undecided |