In situ observation and reduction of hot-cracks in laser additive manufacturing

Yunhui Chen; Duyao Zhang; Patrick O’Toole; Dong Qiu; Marc Seibold; Klaus Schricker; Jean-Pierre Bergmann; Alexander Rack; Mark Easton

doi:10.1038/s43246-024-00522-3

In situ observation and reduction of hot-cracks in laser additive manufacturing

Yunhui Chen, Duyao Zhang, Patrick O’Toole, Dong Qiu, Marc Seibold, Klaus Schricker, Jean-Pierre Bergmann, Alexander Rack, Mark Easton

Research output: Contribution to journal › Article › peer-review

4 Citations (SciVal)

Abstract

Cracking during Laser Additive Manufacturing is a problem for many higher-strength aluminium alloys, including AA6061. Here, we used a pulsed laser with ramp-down power modulation to improve the cracking resistance by about 50% compared to the use of a rectangular pulsed laser. Using synchrotron in situ X-ray imaging at 100,000 images s ⁻¹, ground truth data was obtained about changes in melt pool geometry, solidification rate, and thermal gradients were calculated. An analytical hot cracking model was developed to show that these changes lead to a decreased hot tear susceptibility. Therefore, laser pulse modulation can be an effective tool to reduce crack susceptibility of alloys. More fundamentally, the results demonstrate that modifying thermal conditions provides a pathway to crack elimination in LAM and the model established in our study sets the foundation for further complex laser manipulation in modifying the printability and resulting mechanical properties of hard-to-process alloys in Laser Additive Manufacturing.

Original language	English
Article number	84
Journal	Communications Materials
Volume	5
Issue number	1
Early online date	25 May 2024
DOIs	https://doi.org/10.1038/s43246-024-00522-3
Publication status	Published - 25 May 2024

Data Availability Statement

The Synchrotron data that support the findings of this study are available at the European Synchrotron with the identifier IH-MA-262, Ref. No. 93212.

Funding

The authors thank the ESRF for the provision of beamtime at ID19 (IH-MA-262). Y.C. acknowledges the support from the RMIT Vice Chancellor\u2019s Senior Research Fellowship. Y.C. acknowledges travel funding (AS/IA231/20264) provided by the International Synchrotron Access Program (ISAP) managed by the Australian Synchrotron, part of ANSTO, and funded by the Australian Government. D.Z. acknowledges the support of the ARC-DECRA grant (Grant number: DE210101503). M.S., K.S., and J.P.B. thank the Free State of Thuringia for funding the project \u201CLeistungszentrum InSignA\u201D (2021 FGI 0010).

Funders	Funder number
RMIT University	AS/IA231/20264
Australian Government	DE210101503, 2021 FGI 0010
European Synchrotron Radiation Facility	IH-MA-262

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Cite this

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AU - Chen, Yunhui

AU - Zhang, Duyao

AU - O’Toole, Patrick

AU - Qiu, Dong

AU - Seibold, Marc

AU - Schricker, Klaus

AU - Bergmann, Jean-Pierre

AU - Rack, Alexander

AU - Easton, Mark

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In situ observation and reduction of hot-cracks in laser additive manufacturing

Abstract

Data Availability Statement

Funding

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