Development of cold isostatic pressing graphite module for a heat-resistant lower hybrid current drive antenna

Abstract

Development of a plasma facing module using Cold Isostatic Pressing Graphite ͑CIPG͒ was successfully achieved for use in driving a heat-resistant Lower Hybrid Current Drive ͑LHCD͒ antenna. A thin stainless film ͑10 m͒, a molybdenum film ͑10 m͒, and a copper film ͑50 m͒ were overlaid on the CIPG materials, the CIPG surfaces were successfully coated with the Cu-layer by diffusion bonding method. This module whose length is 206 mm, has four waveguides, and a water cooling channel. High rf-power long pulse operations with water cooling were successfully tested up to 250 kW ͑125 MW/ m 2 ͒ / 700 s, a stationary temperature and vacuum pressure was performed. But the maximum rf transmission power was limited to 47 MW/ m 2 for a plasma facing module using Carbon Fiber Composite ͑CFC͒ due to poor Cu-plating, a power density large by more than a factor 2.5 was achieved with the CIPG module. The rf power density which meets the requirement of the rf electric field of 5 kV/ cm for a design of the LHCD antenna in International Thermonuclear Experimental Reactor ͑ITER͒ was successfully performed.

Low Temperature Casting of Graphene with High Compressive Strength

“…3 orders of magnitude higher than that of previously reported 3‐D graphene 21. Compared with conventional strategies for forming 3D shapes from graphite powder,30–34 the method of this study allows to produce desired shapes via moulding in a single‐step, low‐cost, time‐ and energy‐saving, and low‐temperature process (180 °C). The CG macrostructures reported herein can thus be expected to promote new applications for graphene and further accelerate the commercialization of graphene‐based products.…”