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Title: Design methodology for functionally graded materials: Framework for considering cracking
In functionally graded materials (FGMs) fabricated using directed energy deposition (DED) additive manufacturing (AM), cracks may form due to interdendritic stress during solidification, the formation of deleterious phases, or the buildup of residual stresses. This study builds on our previously proposed concept of FGM feasibility diagrams to identify gradient pathways that avoid deleterious phases in FGMs by also considering hot cracking. Here, five hot cracking criteria were integrated into the feasibility diagrams, and equilibrium simulations were carried out based on Scheil results (termed hybrid Scheil-equilibrium simulation) to predict phase formation below the solidus temperature considering solidification micro-segregation. The new feasibility diagrams were applied to four previously studied FGMs, and the newly proposed approach predicted high crack susceptibility, detrimental phase formation, or interdendritic BCC phase formation in the experimentally observed cracking region. This demonstrates the utility of the proposed framework for crack prediction in the design of future FGMs gradient pathways.  more » « less
Award ID(s):
2050069
PAR ID:
10496307
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Additive Manufacturing
Volume:
73
Issue:
C
ISSN:
2214-8604
Page Range / eLocation ID:
103672
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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