T 44 The effects of sulfur and other impurities on carbon-graphite transition [] / V. A. Tyumentsev, E. A. Belenkov, G. P. Shveikin, S. A. Podkopaev // Carbon. - 1998. - V. 36, N 7-8. - С. 845-853 . - ISSN 0008-6223 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): КОКС -- ГРАФИТИЗАЦИЯ -- ДИФРАКЦИЯ РЕНТГЕНОВСКАЯ -- РЕНТГЕНОВСКАЯ ДИФРАКЦИЯ -- ПЕРЕХОДЫ ФАЗОВЫЕ -- ФАЗОВЫЕ ПЕРЕХОДЫ -- ЖЕЛЕЗО -- ХРОМ -- СЕРА -- S -- Fe -- Cr -- ПЕРЕХОД УГЛЕРОД-ГРАФИТ -- МИКРОСКОПИЯ ЭЛЕКТРОННАЯ -- ЭЛЕКТРОННАЯ МИКРОСКОПИЯ Аннотация: The transition to graphite of carbons containing sulfur and the effects of added iron and chromium on this process have been studied using X-ray diffraction analysis and electron microscopy. It was found that after heat treatment in the temperature interval 1300-1600°C carbons containing at least 1.5 mass% of sulfur, or 0.3 mass% of sulfur and 1.5 mass% of added Cr2O3 become heterogeneous; they consist of an ultradisperse matrix and of large (> 100 nm) and sufficiently perfect (Deltad/d002 ~ 0.002) regions of coherent scattering with interlayer spacing d002 that corresponds to the graphite-crystal structure. When disperse iron is added, the amount of the graphite phase in this temperature interval decreases by a factor of 2 |