AccScience Publishing / MSAM / Volume 3 / Issue 2 / DOI: 10.36922/msam.3088

The role of graded layers in interfacial characteristics and mechanical properties of Ti6Al4V/AlMgScZr-graded multi-material parts fabricated using laser powder bed fusion

Guangjing Huang1 Dongdong Gu1* Hong Liu1 Kaijie Lin1 Rui Wang1 He Sun1
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1 Jiangsu Provincial Engineering Research Center for Laser Additive Manufacturing of High-Performance Metallic Components, College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu, China
Submitted: 5 March 2024 | Accepted: 17 April 2024 | Published: 10 May 2024
© 2024 by the 2024 Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( )

Graded multi-material parts achieve a compositionally graded transition between two different materials, mitigating undesirable consequences such as cracking and delamination due to property mismatch and significantly improving the comprehensive performance of parts. In this study, the Ti6Al4V/AlMgScZr-graded multi-material parts were fabricated using laser powder bed fusion technology, introducing a composition-graded layer with 25 wt.% Ti6Al4V and 75 wt.% AlMgScZr at the interface to reduce the mismatch between the two materials. The effect of the graded layer’s laser scanning speed on the densification behavior, microstructure evolution, and mechanical properties of the Ti6Al4V/AlMgScZr-graded multi-material parts was investigated. It was revealed that the crack area at the interface reduced from 0.325 to 0.067 mm2 as the scanning speed increased from 2400 to 2800 mm/s and then increased to 0.161 mm2 at 3000 mm/s. A smooth, continuous-graded layer with good metallurgical bonding was fabricated at 2800 mm/s. The TiAl3 intermetallic compound was formed at the interface and underwent a transition from rod-like to coarse dendritic and finally to finer dendritic structure along the building direction. The Ti6Al4V/AlMgScZr-graded multi-material parts exhibited a graded decrease in microhardness from 374 HV0.2 on the Ti6Al4V side to 122 HV0.2 on the AlMgScZr side, and an excellent compressive strength of 1531 MPa was obtained at the optimal parameter of 2800 mm/s.

Laser powder bed fusion
Graded multi-material parts
Intermetallic compound
The authors gratefully acknowledge the funding support from National Key Research and Development Program (No. 2023YFB4603300 and 2023YFB4603304), the National Natural Science Foundation of China (No. 52225503), the Key Research and Development Program of Jiangsu Province (No. BE2022069 and No. BE2022069- 1), and the National Natural Science Foundation of China for Creative Research Groups (Grant No. 51921003).
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Conflict of interest
The authors declare that they have no (potential) conflicts or competing interests with any institutes, organizations, or agencies that might influence the integrity of results or objective interpretation of their submitted works to disclose.
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Materials Science in Additive Manufacturing, Electronic ISSN: 2810-9635 Published by AccScience Publishing