EAST In-Vessel Components: from Graphite to Molybdenum

After 10 months hard work, the first wall of EAST in-vessel components has been changed to molybdenum (Mo) tiles from graphite ones at the beginning of this year, the third upgrade of in-vessel components since its construction.

　  Plasma facing components (PFCs) are important components, which protect the vacuum vessel, heating systems and diagnostic components from plasma particles and heat loads. EAST’s first  PFCs were made of stainless steel during 2006- 2007; after two experiment campaigns, to meet the experiment request of long pulse operation with higher power injection, all the PFCs had been upgraded to full graphite tiles in 2008. These tiles are bolted to copper alloy heat sink with actively cooled channels. Now after five campaigns, they have been changed to Mo tiles. With the new tiles’ help, particles recycling from first wall to the plasma will be reduced.

　  Some other revampment works have been done: renewing the joint of heat sink water pipe, using  a new type of multiunit tube brazed with copper and stainless steel.

　  This update of EAST in-vessel components has been accepted by the review panel, and it is expected to give strong support to EAST H mode and long pulse operation in this coming March.（Li Jun and Ji Xiang Report）



Prof. Li Jiangang check the vacuum vessel



EAST in-vessel components