Title: Melt-Pool Dynamics and Microstructure of Mg Alloy WE43 under Laser Powder Bed Fusion Additive Manufacturing Conditions

Abstract

Magnesium-based alloy WE43 is a state-of-the-art bioresorbable metallic implant material. There is a need for implants with both complex geometries to match the mechanical properties of bone and refined microstructure for controlled resorption. Additive manufacturing (AM) using laser powder bed fusion (LPBF) presents a viable fabrication method for implant applications, as it offers near-net-shape geometrical control, allows for geometry customization based on an individual patient, and fast cooling rates to achieve a refined microstructure. In this study, the laser–alloy interaction is investigated over a range of LPBF-relevant processing conditions to reveal melt-pool dynamics, pore formation, and the microstructure of laser-melted WE43. In situ X-ray imaging reveals distinct laser-induced vapor depression morphology regimes, with minimal pore formation at laser-scan speeds greater than 500 mm/s. Optical and electron microscopy of cross-sectioned laser tracks reveal three distinct microstructural regimes that can be controlled by adjusting laser-scan parameters: columnar, dendritic, and banded microstructures. These regimes are consistent with those predicted by the analytic solidification theory for conduction-mode welding, but not for keyhole-mode tracks. The results provide insight into the fundamental laser–material interactions of the WE43 alloy under AM-processing conditions and are critical for the successful implementation of LPBF-produced WE43 parts in biomedical applications.

Authors:

Soderlind, Julie; Martin, Aiden A. ;

• Search DOE PAGES for author "Martin, Aiden A."
• Search DOE PAGES for ORCID "0000-0003-2362-5524"

Calta, Nicholas P. ;

• Search DOE PAGES for author "Calta, Nicholas P."
• Search DOE PAGES for ORCID "0000-0002-6327-6640"

DePond, Philip J. ;

• Search DOE PAGES for author "DePond, Philip J."
• Search DOE PAGES for ORCID "0000-0003-1294-1492"

Wang, Jenny; Vrancken, Bey ;

• Search DOE PAGES for author "Vrancken, Bey"
• Search DOE PAGES for ORCID "0000-0001-6266-9816"

Schäublin, Robin E. ;

• Search DOE PAGES for author "Schäublin, Robin E."
• Search DOE PAGES for ORCID "0000-0002-8379-9705"

Basu, Indranil; Thampy, Vivek; Fong, Anthony Y.; Kiss, Andrew M.; Berry, Joel M.; Perron, Aurélien; Nelson Weker, Johanna ;

• Search DOE PAGES for author "Nelson Weker, Johanna"
• Search DOE PAGES for ORCID "0000-0001-6856-3203"

Stone, Kevin H.; Tassone, Christopher J.; Toney, Michael F.; Van Buuren, Anthony; Löffler, Jörg F. ;

• Search DOE PAGES for author "Löffler, Jörg F."
• Search DOE PAGES for ORCID "0000-0003-2825-6027"

Risbud, Subhash H.

• Search DOE PAGES for author "Risbud, Subhash H."
• Search DOE PAGES for ORCID "0000-0002-4294-032X"

more »; Matthews, Manyalibo J. « less

Publication Date:

Wed Oct 12 00:00:00 EDT 2022

Research Org.:

SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL); Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)

Sponsoring Org.:

USDOE Office of Energy Efficiency and Renewable Energy (EERE); USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE Laboratory Directed Research and Development (LDRD) Program; University of California

OSTI Identifier:

1892088

Alternate Identifier(s):

OSTI ID: 1987687; OSTI ID: 1991621; OSTI ID: 2007275

Report Number(s):

LLNL-JRNL-811193
Journal ID: ISSN 2073-4352; CRYSBC; PII: cryst12101437

Grant/Contract Number:  

18-SI-003; CPA Agreement Numbers 32035, 32037, and 32038; AC52-07NA27344; AC02-76SF00515; LGF-17-476556

Resource Type:

Published Article

Journal Name:

Crystals

Additional Journal Information:

Journal Name: Crystals Journal Volume: 12 Journal Issue: 10; Journal ID: ISSN 2073-4352

Publisher:

MDPI AG

Country of Publication:

Germany

Language:

English

Subject:

36 MATERIALS SCIENCE; additive manufacturing; magnesium; laser powder bed fusion; X-ray imaging; electron microscopy; microstructure