Poster (After Call)

FZJ-2022-05998

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png High heat flux testing results of various W-FGM-steel joints

Ganesh, V. (Corresponding author)FZJ* ; Dorow-Gerspach, D.FZJ* ; Matejicek, J. ; Vilemova, M. ; Bram, M.FZJ* ; Coenen, J. W.FZJ* ; Wirtz, M.FZJ* ; Pintsuk, G.FZJ* ; Theisen, W. ; Linsmeier, C.FZJ*

2022

Please use a persistent id in citations: http://hdl.handle.net/2128/33236

Abstract: For a future commercial fusion reactor the First Wall of the breeding blanket will require a joint between the structural steel and the plasma facing material tungsten. However, the difference in the coefficient of thermal expansion (CTE) between them results in thermal stresses at their interface during operation and this could result in premature failure of the joint. A functionally graded material (FGM), as an interlayer between tungsten and steel could reduce these stresses. In this study two processes, atmospheric plasma spraying (APS) and spark plasma sintering (SPS), are utilized to manufacture four different kinds of W-FGM-steel stacks: the first two include FGMs prepared by APS; W-V-75W-50W-25W-steel and W-50W-25W-steel, the other two include FGMs made by SPS; W-75W-50W-25W-steel and W-50W-25W-steel. This investigates: i) the influence of an additional V-interlayer; ii) the comparison of APS- and SPS-FGMs; and iii) the influence of FGM composition and thickness. In all these W-FGM-steel stacks, with a surface area of 12 mm x 12 mm, the thickness of each FGM sublayer (75W, 50W, 25W) is about 0.5 mm, whereas the bulk-W and bulk-steel are 3 mm thick. A sample of direct diffusion bonded W-steel joint is used as a reference. A high heat flux benchmark test was performed to investigate and compare the potential of the different joining technologies. For this, the stacks were soldered on a copper cooling module and exposed to high stationary loads at the JUDITH-2 facility. At each power level of 1 MW/m2, 2 MW/m2, 3 MW/m2 and 4 MW/m2 the samples were subjected to a component screening cycle to determine the component quality followed by up to 200 on/off cycles (30/30 s). By monitoring the surface temperature using an IR camera, the cooling capabilities of each sample and any local overheating as indication of bond failure can be determined.

Keyword(s): Energy (1st) ; Engineering, Industrial Materials and Processing (1st)

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Contributing Institute(s):

1. Plasmaphysik (IEK-4)

Research Program(s):

1. 133 - Technologien und Materialien für die Fusion (POF4-133) (POF4-133)

Appears in the scientific report 2022

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Database coverage:

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