ITER divertor sputtering erosion: Recent analysis for carbon, beryllium, tungsten, and niobium surfaces

ITER divertor plate sputtering erosion has been analyzed using current design information and updated impurity transport models. The REDEP erosion/redeposition code was used to compute erosion for a very low plasma divertor temperature (T sub e sub 0 approx. 12 eV) physics phase reference case, and for other plasma conditions. A high surface temperature case (T sub s sub 0 = 1800 C) is analyzed for a carbon surface. Niobium is analyzed using WBC near-surface transport code results for the redeposited charge state. The REDEP results show high net erosion rates approx. greater than 20 cm/burn(sm bullet)yr for beryllium and carbon, even at low plasma temperatures. Net erosion rates are low to moderate for niobium (approx. 0 to 3 cm/burn(sm bullet)yr), depending on plasma conditions, and low for tungsten (approx. 0 to 0.2 cm/burn(sm bullet)yr).