Local composition detouring for defect-free compositionally graded materials in additive manufacturing

Abstract

This study investigated cracking phenomena in 316L stainless steel (SS316L) and Inconel 718 (IN718) composition-graded material (CGM) additively manufactured by the direct energy deposition (DED) process. In order to prevent cracking in the CGM, thermodynamic analysis was performed to avoid the critical concentration for crack formation. Based on the local compositional detouring (LCD) method suggested by new approach, a crack-free CGM with a nonlinear combination of SS316L and IN718 was successfully fabricated with local additional elemental powder in the CGM defective region obtained using a multi-powder feeding system during the DED process.

GRAPHICAL ABSTRACT

IMPACT STATEMENT

We aim to avoid the cracks of functionally graded materials fabricated by local in-situ alloying technique using the result of thermodynamically analyzing.

KEYWORDS:

• Additive manufacturing
• crack formation
• functionally graded materials
• in-situ alloying
• local composition detouring

Acknowledgments

Eun Seong Kim was supported by the Basic Science Research Program ‘Fostering the Next Generation of Researchers (Ph.D. Candidate)’ through the NRF funded by the Ministry of Education (2022R1A6A3A13073830).

Data availability

The raw/processed data required to reproduce these findings cannot be shared at this time as the data also forms part of an ongoing study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Research Foundation of Korea (NRF) grant funded (2022R1A5A1030054 and 2021R1A2C3006662). This work was also supported by Principal R&D Project (PNK8290) of the Korean Institute of Materials Science (KIMS), and Basic Research Program (PICO190) of Korea Institute of Machinery and Materials (KIMM). Eun Seong Kim was supported by the Basic Science Research Program ‘Fostering the Next Generation of Researchers (Ph.D. Candidate)’ through the NRF funded by the Ministry of Education (2022R1A6A3A13073830).