Zhendong Jia , Qiaonan Shu , Biao Chen , Fangqi Liu , Lei Jia , Pingxiang Zhang , Jinshan Li
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引用次数: 0
Abstract
Laser powder bed fusion (LPBF) provides high design freedom for high-strength aluminum alloys in aerospace and automotive industries. However, the rapid solidification of LPBF results in a critical microstructural challenge in aluminum alloys: coarse columnar grains with anisotropy and cracking. In this work, we employ the synergistic effect of magnesium and titanium elements in aluminum alloys for building self-assembled MgAl2O4/Al3Ti hierarchical architectures as a highly efficient nucleation agent. In-situ MgAl2O4 nanoparticles offer coherent interfaces (lattice mismatch: 0.05 %) for the nucleation of L12-structured Al3Ti phase, facilitating the formation of fully equiaxed grains with random orientations in aluminum alloys. Aberration-corrected transmission electron microscopy demonstrates atomic-scale coherence at MgAl2O4/Al3Ti interfaces, confirming MgAl2O4 as effective nucleation substrates for Al3Ti phase. Our study provides a new microstructure-design strategy for LPBF, achieving aluminum alloys with fully equiaxed grains.
期刊介绍:
Scripta Materialia is a LETTERS journal of Acta Materialia, providing a forum for the rapid publication of short communications on the relationship between the structure and the properties of inorganic materials. The emphasis is on originality rather than incremental research. Short reports on the development of materials with novel or substantially improved properties are also welcomed. Emphasis is on either the functional or mechanical behavior of metals, ceramics and semiconductors at all length scales.