Development of ITER Divertor Vertical Target with Annular Flow Concept - II: Development of Brazing Technique for CFC/CuCrZr Joint and Heating Test of Large-Scale Mock-Up

Journal Article · Wed Dec 15 04:00:00 EST 2004 · Fusion Science and Technology

OSTI ID:20849767

Ezato, K ^[1]; Dairaku, M ^[1]; Taniguchi, M ^[1]; Sato, K ^[1]; Suzuki, S ^[1]; Akiba, M ^[1]; Ibbott, C ^[2]; Tivey, R ^[2]

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1. Japan Atomic Energy Research Institute (Japan)
2. ITER Garching Joint Work Site (Germany)

The first fabrication and heating test of a large-scale carbon-fiber-composite (CFC) monoblock divertor mock-up using an annular flow concept has been performed to demonstrate its manufacturability and thermomechanical performance. This mock-up is based on the design of the lower part of the vertical target of the International Thermonuclear Experimental Reactor (ITER) divertor adapted for the annular flow concept. The annular cooling tube consists of two concentric tubes: an outer tube made of CuCrZr and an inner stainless steel tube with a twisted external fin. Prior to the fabrication of the mock-up, brazed joint tests between the CFC monoblock and the CuCrZr tube have been carried out to find the suitable heat treatment mitigating loss of the high mechanical strength of the CuCrZr material. A basic mechanical examination of CuCrZr undergoing the brazing heat treatment and finite element method analyses are also performed to support the design of the mock-up. High heat flux tests on the large-scale divertor mock-up have been performed in an ion beam facility. The mock-up has successfully withstood more than 1000 thermal cycles of 20 MW/m{sup 2} for 15 s and 3000 cycles of >10 MW/m{sup 2} for 15 s, which simulates the heat load condition of the ITER divertor. No degradation of the thermal performance of the mock-up has been observed throughout the thermal cycle test although in the tile with exposure to the heat flux of 20 MW/m{sup 2}, the erosion depth has been measured as 5.8 and 8.8 mm at the 300th and 500th cycles.

• OSTI ID: 20849767
• Journal Information: Fusion Science and Technology, Journal Name: Fusion Science and Technology Journal Issue: 4 Vol. 46; ISSN 1536-1055
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
BRAZED JOINTS
CARBON FIBERS
DESIGN
DIVERTORS
EROSION
FINITE ELEMENT METHOD
HEAT FLUX
HEAT TREATMENTS
HEATING
ION BEAMS
ITER TOKAMAK
PERFORMANCE
STAINLESS STEELS
THERMONUCLEAR REACTOR MATERIALS
TUBES