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Title: Creep Properties of Gas Metal Arc Directed Energy Deposition Austenitic Stainless Steel
Abstract Gas metal arc directed energy deposition (GMA-DED) has potential for the power generation industry to reduce both time and cost since larger and more complex part geometries can be constructed compared to the typical subtractive methods. The performance of GMA-DED builds can be influenced by the deposition method, resulting microstructure, and formation of defects or secondary phases in the final component. Previous work in the literature evaluated the mechanical properties of GMA-DED builds for a range of austenitic stainless steels, however there is limited data on the high temperature mechanical behavior. This work evaluated the high temperature creep properties of GMA-DED builds constructed with type 316H, 316L, 316LSi, and 16-8-2 stainless steels at 650 °C, 750 °C and 825 °C. The alloy with longest time to rupture for a given stress varied depending on test temperature. Creep damage accumulation at grain boundaries was observed along with grain boundary precipitates which likely aided in damage accumulation. Evaluating the creep properties with the Larson-Miller parameter showed the majority of results fell within the scatter band of creep performance for wrought 316 alloys, indicating the GMA-DED process may be suitable for use in advanced energy systems.  more » « less
Award ID(s):
2052819
PAR ID:
10609345
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
American Society of Mechanical Engineers
Date Published:
ISBN:
978-0-7918-8850-6
Format(s):
Medium: X
Location:
Bellevue, Washington, USA
Sponsoring Org:
National Science Foundation
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