This title appears in the Scientific Report :
2020
Please use the identifier:
http://dx.doi.org/10.1016/j.nimb.2020.06.005 in citations.
Please use the identifier: http://hdl.handle.net/2128/25217 in citations.
Temporally resolved LEIS measurements of Cr segregation after preferential sputtering of WCrY alloy
Temporally resolved LEIS measurements of Cr segregation after preferential sputtering of WCrY alloy
The dynamic behaviour of thermally driven segregation of Cr to the surface of WCrY smart alloy is studied with low energy ion scattering (LEIS). Sputtering the WCrY sample with 500 eV ions at room temperature results in preferential removal of the lighter alloy constituents and causes an almost pure...
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Personal Name(s): | Koslowski, H. R. (Corresponding author) |
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Schmitz, Janina / Linsmeier, Ch. | |
Contributing Institute: |
Plasmaphysik; IEK-4 |
Published in: | Nuclear instruments & methods in physics research / B Beam interactions with materials and atoms, 479 (2020) S. 42 - 46 |
Imprint: |
Amsterdam [u.a.]
Elsevier
2020
|
DOI: |
10.1016/j.nimb.2020.06.005 |
Document Type: |
Journal Article |
Research Program: |
Methods and Concepts for Material Development |
Link: |
Published on 2020-06-18. Available in OpenAccess from 2022-06-18. Published on 2020-06-18. Available in OpenAccess from 2022-06-18. |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/25217 in citations.
The dynamic behaviour of thermally driven segregation of Cr to the surface of WCrY smart alloy is studied with low energy ion scattering (LEIS). Sputtering the WCrY sample with 500 eV ions at room temperature results in preferential removal of the lighter alloy constituents and causes an almost pure W surface layer. At elevated temperatures above 700 K the segregation of Cr atoms towards the surface sets in and prevents the formation of a pure W layer. The simultaneous heating and sputtering of the sample leads to a surface state which reflects the balance between sputter removal and segregation flux, and deviates from the equilibrium due to thermally driven segregation. Stopping the sputter ion beam allows the system to relax and develop toward the segregation equilibrium. The time constants for the temporal changes of W and Cr surface coverage are obtained from a series of LEIS measurements. The segregation enthalpy is determined from the time constants obtained for various sample temperatures. |