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  • Effect of heat treatment on functionally graded 304L stainless steel to Inconel 625 fabricated by directed energy deposition
Title: Effect of heat treatment on functionally graded 304L stainless steel to Inconel 625 fabricated by directed energy deposition
Defining heat treatments for compositionally functionally graded materials (FGMs) is challenging due to varying processing conditions in terminal alloys and gradient regions. In the present work, we studied the impact of heat treatments on phase transformations and the resulting mechanical properties along an FGM grading from stainless steel 304L (SS304L) to Inconel 625 (IN625) FGM fabricated using directed energy deposition (DED) additive manufacturing (AM). We applied heat treatments at 700 °C, 900 °C, and 1150 °C and the microstructure and hardness, as a function of layer-wise composition and applied heat treatment, were characterized. The applicability of computational methods previously developed by the team to predict experimentally observed phases by the hybrid Scheil-equilibrium approach was evaluated. This approach improves the accuracy of predicting phases formed after heat treatment compared to equilibrium thermodynamic calculations using the overall layer compositions and provides a simple pathway to assist in designing heat treatment for FGMs.  more » « less
Award ID(s):
2050069
PAR ID:
10496305
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Materialia
ISSN:
2589-1529
Page Range / eLocation ID:
102067
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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