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Title: Design of crack-free laser additive manufactured Inconel 939 alloy driven by computational thermodynamics method

This paper examined the effect of Si addition on the cracking resistance of Inconel 939 alloy after laser additive manufacturing (AM) process. With the help of CALculation of PHAse Diagrams (CALPHAD) software Thermo-Calc, the amounts of specific elements (C, B, and Zr) in liquid phase during solidification, cracking susceptibility coefficients (CSC) and cracking criterion based on$$\left| {{\text{d}}T/{\text{d}}f_{{\text{s}}}^{1/2} } \right|$$dT/dfs1/2values (T: solidification temperature,fs: mass fraction of solid during solidification) were evaluated as the indicators for composition optimization. It was found that CSC together with$$\left| {{\text{d}}T/{\text{d}}f_{{\text{s}}}^{1/2} } \right|$$dT/dfs1/2values provided a better prediction for cracking resistance.

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Award ID(s):
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Cambridge University Press (CUP)
Date Published:
Journal Name:
MRS Communications
Page Range / eLocation ID:
p. 844-849
Medium: X
Sponsoring Org:
National Science Foundation
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