Thermal Diffusivity and Thermal Conductivity of Carbon Materials for Tokamak Limiters

  • E. P. Roth
  • M. Moss


A plasma limiter is used to control the plasma size in Tokamak fusion research devices and serves as one of the main areas of plasma wall interaction. Wall temperatures can reach as high as 3000 K resulting in significant sputtering and wall erosion. Graphite and graphite composites have been chosen as the materials which best meet the requirements of this severe environment. The thermal conductivities of these materials are critical to the modeling of the thermophysical response of the limiters during operation. The thermal conductivities of several candidate materials were measured. Three categories of materials were investigated in this study: pyrolytic graphite and annealed pyrolytic graphite; carbon/carbon fiber composites composed of two- directionally woven fibers with a graphitized pitch matrix; carbon/carbon fiber composites with a four-directional carbon fiber weave. The thermal conductivities of the carbon/carbon fiber composites were determined as a function of fiber orientation. Conductivities were measured using both the laser flash diffusivity technique and the thermal comparative method. The advantages and disadvantages of each of these methods will be discussed and the data compared.


Thermal Conductivity Fiber Composite Pyrolytic Graphite Sandia National Laboratory Radial Heat Flow 
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Copyright information

© Purdue Research Foundation 1989

Authors and Affiliations

  • E. P. Roth
    • 1
  • M. Moss
    • 1
  1. 1.Thermophysical Properties DivisionSandia National LaboratoriesAlbuquerqueUSA

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