Effect of plasma-sintering consolidation on the reactivity of beryllium

Kim, Jae-Hwan; Nakamichi, Masaru

Beryllide is a promising candidate as advanced neutron multiplier owing to higher stability and lower reactivity at high temperature. It was clarified in the previous studies on synthesis of beryllide that plasma sintering as non-conventional consolidation process could easily and rapidly synthesize the beryllide. In this study, to evaluate the effect of the plasma sintering consolidation of the material on fundamental property, the reactivity with oxygen at high temperature was examined using beryllium metals. The plasma-sintered beryllium was prepared for comparison of commercial grades of berylliums, that is, S65C and S65E, because it is well-known that the plasma sintering can facilitate to not only eliminate impurities but activate the powder surface due to applying a pulse current. The weight gain and optical surface observation result obviously clarified that the Be-PS and S65E exhibited the higher oxidation resistance than S65C which has larger grain size. Accordingly, it was obvious that the smaller grain size the beryllium has, the better oxidation resistance it has. In addition, the electron probe micro-analysis clearly proved that impurity was apt to be intensively located near grain boundary as an oxide type and the Be-PS contained less impurity than others. Therefore not only grain size but also impurity seems to have a close correlation on reactivity at the high temperature.