The influence of low dose neutron irradiation on the paramagnetic properties of cubic boron nitride micropowders / L.I. Azarko, L.A. Karpovich, E.l. Kozlova, O.N. Yankovsky, O.A. Ignatenko, A.G. Dutov, V.B. Shipilo

В работе исследовались микрокристаллические порошки кубического нитрида бора, синтезированные в различных каталитических системах роста. Установлены особенности дефектообразования в образцах в зависимости от условий синтеза и последующего нейтронного воздействия. Показано, что облучение в горизонтальном канале реактора ИБР-2 нейтронами с отношением плотности потока быстрых к тепловым равным 3,34, вызывает увеличение в 2 раза концентрации парамагнитных центров в микропорошках, синтезированных в каталитической системе с дополнительным введением боросодержащей добавки.The micropowders of the cubic boron nitride grown in dolomite containers under 5,5 GPa and 1620 K were investigated in the present work Li3N was used as a catalyst. Its amount was being changed from 4 up to 10% of the total mass of the furnace charge. There was a boron-containing admixture added to the furnace charge, in the case of the catalyst-to-cBN ratio 1:10, at the rate of 0 - 5% of the total mass of the reagents. The crystals synthesis was conducted in the direct furnace charge heating regime within 5 seconds. It was found that some characteristics of the defects formation in the studied samples depend on the synthesis and further neutron irradiation conditions. The irradiation with neutrons was conducted In the horizontal channel of the reactor. It was shown that the irradiation of the micropowders with neutrons, having the relation of the fast to thermal neutrons flow densities equal to 3,34, causes the paramagnetic centers concentration increase (by the factor of two) in the samples synthesized in the catalytic system having an additional boron-containing admixture