Applied physics
N 1, 2003

Research tritium penetration in first wall materials of nuclear fusion reactor with magnetic microscope help

E. A. Azizov, A. I. Markin, N. I. Siromjatnikov, V. E. Cherkovets
SRC RF TRINITI, Troitsk, Russia

N. N. Riazantseva, V. N. Tebus
SRC RF VNIINM, Moscow, Russia

   Results of the research installation of tritium distribution and diffusion are presented in this paper. The sample of materials made out of a molibdenium with raising dust layer of titanium. The thickness of titanium layer is ~7 mkm with tritium concentration up to ~10²² см^-3. Measurementes of the tritium concentration distribution were done due to its b-activity with help magnetic microscope. The microscope permits to obtain two-dimension distributions of b-electron emission with high sensitivity and resolution as well as to have enlarged images on the film or screen electron-optic converter. The method of autoradiography was used also for registration twodimension distribution secondary X-rays at the film. Measurements has given (in electron rays) the tritium distribution in surface titanium layer with thickness < 1 mkm. Heterogeneity of the distribution was discovered. The relative concentration of tritium was changed about three times. There were receivered (in X-rays) the tritium distribution and its supply in deep layer (10—20 mkm) with good homogeneity (heterogeneity smaller 10 %). It was obtained the tritium concentration distribution as function of deepness using cut of the sample cross-section and layer-disposal. Boundary-layer (<1 mkm) at the external side of the titanium surface was discovered where the titanium concentration is smaller 2—3 times than for depth (and another sample ~10 times). The tritium diffusion from the titanium layer (where it was saturated) to the molibdenium is about 50—70 %. It was shown, that tritium concentration in molibdenium near the boundary-layer titanium—molibdenium is not smaller than in titanium.

Contents