RETENTION OF DEUTERIUM IMPLANTED INTO B4C-OVERLAID ISOTROPIC GRAPHITES AND HOT-PRESSED B4C

Retention characteristics of two kinds of B4C-overlaid graphites and hot-pressed B4C were investigated. An ion beam of 3 keV D2+ was implanted into the specimens at room temperature. The amount of retained deuteriums was measured as function of the implantation fluence and temperature by elastic recoil detection analysis. Thermal release behavior of implanted deuteriums was also measured by isochronal annealing. The concentration of retained, deuterium reaches saturation similarly in three kinds of B4C-overlaid specimens at the fluences over 10(18) D+/cm2 as in isotropic graphite. The release temperature, at which the number of retained deuterium decreases to one half in isochronal annealing, are about 250 K lower for three kinds of B4C specimens than for graphite. The release temperature of deuterium from unsaturated hot-pressed B4C in isochronal annealing is about 500 K higher than that from saturated one.