Study of the surface features on the TFTR inner limiter using a frequency modulated coherent laser radar device developed for ITER

A frequency modulated coherent laser radar (FM CLR) device was designed for remote metrology and inspection of plasma facing components in ITER. A proof-of-principle version of the device, capable of operating under exvessel atmospheric conditions, was utilized to study the surface features of the TFTR inner limiter tiles. Flaking of co-deposited hydrogenated carbon layers was observed on these graphite tiles. The cause of this flaking is not yet clear, but the flaking has major implications from the point of reactor operation and tritium inventory. Measurements were made on the tiles to elucidate the flaking phenomena