ЕВОЛЮЦІЯ КЛАСТЕРА ПРОСОЧЕННЯ В ПОРОШКУ КУБІЧНОГО BN ЗА ВИСОКОГО ТИСКУ ПРИ НАГРІВАННІ

Ігор Петруша; Osipov Alexander; Yurii Mel’niichuk; OleksandrBorymskyi Borymskyi; Tamara Smirnova; Vasilii  Tkach; Nadiia   Belyavina

Ігор Петруша Інститут надтвердих матеріалів ім. В. М. Бакуля НАН України
Osipov Alexander Department of superhard materials creation at high pressures, V. N. Bakul Institute for superhard materials of the National Academy of Sciences of Ukraine, Avtozavodska str., 2, Kyiv, Ukraine, 04074
Yurii Mel’niichuk Department of Technological Control of Surface Quality, V. N. Bakul Institute for superhard materials of the National Academy of Sciences of Ukraine, Avtozavodska str., 2, Kyiv, Ukraine, 04074
OleksandrBorymskyi Borymskyi Department of high pressures technology, functional ceramics composites and dispersive superhard materials
Tamara Smirnova Department of superhard materials creation at high pressures, V. N. Bakul Institute for superhard materials of the National Academy of Sciences of Ukraine, Avtozavodska st., 2, Kyiv, Ukraine, 04074
Vasilii Tkach Department of Research of physico-chemical processes of superhard materials synthesis and their structure, V. N. Bakul Institute for superhard materials of the National Academy of Sciences of Ukraine, Avtozavodska str., 2, Kyiv, Ukraine, 04074
Nadiia Belyavina Faculty of Physics, Department of Physics of Metals, Taras Shevchenko National University of Kyiv, Acad. Glushkova av., 4, 03127 Kyiv, Ukraine

Keywords: cubic boron nitride (cBN), diamond, high pressure and high temperature (HPHT), percolation cluster, melt infiltration, structure consolidation, composite

Abstract

The evolution of the percolation cluster (PC) in compressed to 7.7 GPa cBN powder of the KM 10/7 (μm) fraction during the gradual increase in temperature from room temperature to 2250 °C was studied. Thermobaric conditions were created in high-pressure toroidal-type HPA/T-30 and HPA/T-20 apparatuses. The nature of the percolation (infusion, infiltration,) of liquid into the compressed cBN powder mass from an external source was studied for both Si melt and melts of non-ferrous metals, such as Al, Ag, Cu, Au and Ni (infiltrants). The maximum temperature in the evolutionary process of PC changes was identified with the melting point of the substance that fills the volume of the percolation cluster. A number of aspects of the formation of the composites structure according to the Koops type of “grains and layers” are discussed: the problem of mixtures, invasive percolation and refining, “poisoning” of the infiltrant. Color images in the article are available on the online resource: www.altis-ism.org.ua

THE EVOLUTION OF THE PERCOLATION CLUSTER IN POWDER OF CUBIC BN AT HIGH PRESSURE DURING HEATING

Abstract