Ji-Yun WangVerner SohPei WangTzu-Ching TsaoMing-Wen ChuMing-Hao LeeZhongji SunSHAO-PU TSAI2024-11-222024-11-222024-12https://www.scopus.com/record/display.uri?eid=2-s2.0-85208141075&origin=resultslisthttps://scholars.lib.ntu.edu.tw/handle/123456789/723205Cellular structures (i.e., solidification cells) are a unique feature within alloys fabricated through rapid solidification, such as laser-powder bed fusion (L-PBF). Ever since the report of these structures’ beneficial effects on the material's mechanical properties, numerous studies have been devoted to the understanding of their formation mechanisms. Yet, the integrity and stability of the cellular structures are often less investigated, despite their significance on property interpretation and evolution. In this work, a stepwise in-situ heating transmission electron microscopy (TEM) experiment was performed on the exemplary LPBF-fabricated AlFeSiMoZr alloy. A critical threshold of 325 °C was identified, beyond which the cellular structures start to decompose in conjunction with precipitate coarsening. Preferred precipitate nucleation sites and their subsequent coarsening kinetics were determined and presented. Nanometer-sized crystalline embryos (3.81 ± 0.66 nm) were discovered within the cellular structure boundaries in their as-built condition, offering new insights on the precipitate formation and evolution at elevated temperatures.true4D STEMAl-Fe alloysAl12(FeMo)3SiCellular structuresEmbryoHRSTEMIn-situ heating TEMLaser-powder bed fusionNucleationThermal stability[SDGs]SDG9journal article10.1016/j.addlet.2024.1002512-s2.0-85208141075