Be-Cu joints based on amorphous alloy brazing for divertor and first wall application
Abstract
The limitation on using silver-based alloys for brazing ITER in-vessel components created a development problem for new brazing materials. An application of Be tiles joined to a Cu-based heat sink will be discussed in this paper. For this purpose, rapidly solidified ribbon-type filler metal STEMET 1108 (Cu-Sn-In-Ni system) with a melting temperature of 750°C and a thickness up to 50 μm was developed. A new temperature regime and heating method were applied during this brazing procedure. This improves the properties of joints significantly, in comparison with conventional brazing in a resistance furnace. These treatments can increase the operational threshold for Be/Cu joints under cyclic surface heat loading up to 12 MW/m 2. Metallographic examinations demonstrated the high quality of brazed joints. The brazed seam has a uniform structure along its entire length. Defects of seam filling, pores, intermetallic compounds and other inclusions are not seen. The prospects of these joints for fusion reactor applications are discussed.
STEMET ® is a registered trade name of MIFI-AMETO, Ltd. It is a company which specialises in producing of ribbon-type brazing filler metals by rapid solidification.- Publication:
-
Journal of Nuclear Materials
- Pub Date:
- 1999
- DOI:
- 10.1016/S0022-3115(98)00796-X
- Bibcode:
- 1999JNuM..271..410K