This title appears in the Scientific Report :
2017
Please use the identifier:
http://dx.doi.org/10.1016/j.nme.2016.06.002 in citations.
Please use the identifier: http://hdl.handle.net/2128/15223 in citations.
Manufacturing and testing of self-passivating tungsten alloys of different composition
Manufacturing and testing of self-passivating tungsten alloys of different composition
Self-passivating tungsten based alloys for the first wall armour of future fusion reactors are expected to provide a major safety advantage compared to pure tungsten in case of a loss of coolant accident with simultaneous air ingress, due to the formation of a stable protective scale at high tempera...
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Personal Name(s): | Calvo, A. |
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García-Rosales, C. (Corresponding author) / Koch, F. / Ordás, N. / Iturriza, I. / Greuner, H. / Pintsuk, G. / Sarbu, C. | |
Contributing Institute: |
Plasmaphysik; IEK-4 |
Published in: | Nuclear materials and energy, 9 (2016) S. 422 - 429 |
Imprint: |
Amsterdam [u.a.]
Elsevier
2016
|
DOI: |
10.1016/j.nme.2016.06.002 |
Document Type: |
Journal Article |
Research Program: |
Plasma-Wall-Interaction |
Link: |
OpenAccess OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/15223 in citations.
Self-passivating tungsten based alloys for the first wall armour of future fusion reactors are expected to provide a major safety advantage compared to pure tungsten in case of a loss of coolant accident with simultaneous air ingress, due to the formation of a stable protective scale at high temperatures in presence of oxygen which prevents the formation of volatile and radioactive WO3.Bulk W-15Cr, W-10Cr-2Ti and W-12Cr-0.5Y alloys were manufactured by mechanical alloying followed by can encapsulation and HIP. This route resulted in fully dense materials with nano-structured grains. The ability of Ti and especially of Y to inhibit grain growth was observed in the W-10Cr-2Ti and W-12Cr-0.5Y alloys. Besides, Y formed Y-rich oxide nano-precipitates at the grain boundaries, and is thus expected to improve the mechanical behaviour of the Y-containing alloy. Isothermal oxidation tests at 800 ºC (1073 K) and oxidation tests under accident-like conditions revealed that the W-12Cr-0.5Y alloy exhibits the best oxidation behaviour of all alloys, especially in the accident-like scenario. Preliminary HHF tests performed at GLADIS indicated that the W-10Cr-2Ti alloy is able to withstand power densities of 2 MW/m2 without significant damage of the bulk structure. Thermo-shock tests at JUDITH-1 to simulate mitigated disruptions resulted in chipping of part of the surface of the as-HIPed W-10Cr-2Ti alloy. An additional thermal treatment at 1600 °C (1873 K) improves the thermo-shock resistance of the W-10Cr-2Ti alloy since only crack formation is observed. |