Design of crack-free laser additive manufactured Inconel 939 alloy driven by computational thermodynamics method
Congyuan Zeng, Huan Ding, Uttam Bhandari, Shengmin Guo
Abstract
Abstract 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 $$\left| {{\text{d}}T/{\text{d}}f_{{\text{s}}}^{1/2} } \right|$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mfenced> <mml:mrow> <mml:mtext>d</mml:mtext> <mml:mi>T</mml:mi> <mml:mo>/</mml:mo> <mml:mtext>d</mml:mtext> <mml:msubsup> <mml:mi>f</mml:mi> <mml:mrow> <mml:mtext>s</mml:mtext> </mml:mrow> <mml:mrow> <mml:mn>1</mml:mn> <mml:mo>/</mml:mo> <mml:mn>2</mml:mn> </mml:mrow> </mml:msubsup> </mml:mrow> </mml:mfenced> </mml:math> values ( T : solidification temperature, f s : mass fraction of solid during solidification) were evaluated as the indicators for composition optimization. It was found that CSC together with $$\left| {{\text{d}}T/{\text{d}}f_{{\text{s}}}^{1/2} } \right|$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mfenced> <mml:mrow> <mml:mtext>d</mml:mtext> <mml:mi>T</mml:mi> <mml:mo>/</mml:mo> <mml:mtext>d</mml:mtext> <mml:msubsup> <mml:mi>f</mml:mi> <mml:mrow> <mml:mtext>s</mml:mtext> </mml:mrow> <mml:mrow> <mml:mn>1</mml:mn> <mml:mo>/</mml:mo> <mml:mn>2</mml:mn> </mml:mrow> </mml:msubsup> </mml:mrow> </mml:mfenced> </mml:math> values provided a better prediction for cracking resistance. Graphical abstract