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Growth of a textured quasicrystalline phase in Ti-Ni-Zr films prepared by pulsed laser deposition

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 نشر من قبل Valerie Brien
 تاريخ النشر 2020
  مجال البحث فيزياء
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 تأليف Valerie Brien




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The preparation in thin film form of the known icosahedral phase in Ti-Ni-Zr bulk alloys has been investigated as a function of substrate temperature. Films were deposited by Pulsed Laser Deposition on sapphire substrates at temperatures ranging from room temperature to 350$^circ$C. Morphological and structural modifications have been followed by grazing incidence and $theta$-2$theta$ X-ray diffraction, transmission electron diffraction and imaging. Chemical composition has been analysed by Electron Probe Micro-Analysis. The in-depth variation of composition has been studied by Secondary Neutral Mass Spectroscopy. We show that Pulsed Laser Deposition at 275$^circ$C makes the formation of a 1 m thick film of Ti-Ni-Zr quasicrystalline textured nanocrystallites possible.



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