摘要
Here we propose to employ electron beam surface melting (EBSM)to refine microstructural length scale and obtain suited microstructure morphology of Nb-Si based alloys. As characterized by scanning transmission electron microscopy (STEM)and atom probe tomography (APT), nano-lamellar eutectics are created in Nb-20Si (at.%)alloys upon EBSM. Theoretical analysis based on the competitive growth models demonstrates the preferred formation of Nb solid solution (Nbss)/Nb3Si eutectics under selected processing parameters. The large cooling rate during EBSM, higher than 8 × 104 K/s, promotes the formation of the nano-scale eutectics. Compared to the initial coarse eutectics by arc melting, simultaneous enhancement of hardness and fracture toughness is enabled owing to the controlled microstructural length scale and morphology.
源语言 | 英语 |
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页(从-至) | 22-27 |
页数 | 6 |
期刊 | Applied Surface Science |
卷 | 486 |
DOI | |
出版状态 | 已出版 - 30 8月 2019 |