SIMULATION OF ION REFLECTION AND SPUTTERING FOR PLASMA-IRRADIATED SOLID-SURFACES IN AN OBLIQUE MAGNETIC-FIELD

A Monte Carlo simulation model is developed for the study of the plasm a-surface interactions in magnetic confinement fusion devices. The emp hasis is put on the understandings of erosion and redeposition process es for wall materials. The model is composed of three parts: (1) low-e nergy Maxwellian ion-solid interaction, (2) ionization of reflected an d sputtered neutral particles in a plasma, acid (3) gyromotion of the resulting ions in an oblique magnetic field and some of the ions are r edeposited on the solid surface. The redeposited particles acquire hea vier masses, and lower charge stares and energies. The redeposition ca uses substantially low effective sputter erosion of heavy materials an d large decrease in tow-energy component of the emitted particles as w ell.