EXPERIMENTAL STUDY OF FIRST MIRROR DEGRADATION UNDER INFLUENCE OF ITER RELEVANT CONDITIONS

摘要

The tests of FM prototypes with reflective coatings were performed, that has allowed to find out their stability under ITER conditions and also to reveal a few imperfections of technology. The initial quality of mirrors was quite satisfactory and some defects were discovered only during long-term sputtering test. The efforts on an improvement of the sputter deposition technology proceed at the moment. The experiments on modelling of contaminating film's deposition have shown an importance of creation of conditions that would be as much as possible similar to the ITER environments, because the properties of mirrors with contamination on a surface do very strongly depend on films chemical composition and structure, which are wholly determined by deposition conditions. The successful tests of a technique of laser cleaning of carbon and hydrocarbon films from the mirror surface were carried out. The diagnostic laser test bench was assembled and the first results on impact of a multi-shot laser radiation on metallic mirrors have been obtained.