ПІДВИЩЕННЯ ЕФЕКТИВНОСТІ РОЗДІЛЕННЯ ЗА ДЕФЕКТНІСТЮ ПОВЕРХНІ ШЛІФПОРОШКІВ АЛМАЗУ У ВОДНОМУ СЕРЕДОВИЩІ

• Date: 2024
• Main Authors: Ільницька, Галина, Лавріненко, Валерій, Логінова, Ольга, Смоквина, Володимир, Соколов, Олександр, Старик, Сергій, Зайцева, Ірина, Закора, Анатолій, Тимошенко, Вікторія, Котинська, Людмила, Косенчук, Тамара
• Format: Article
• Language: Ukrainian
• Published: Институт сверхтвердых материалов им. В. Н. Бакуля Национальной академии наук Украины 2024
• Subjects: характеристики міцності синтетичних алмазів; однорідність шліфпорошків алмазу за міцністю; розділення за величиною дефектності поверхні
• Online Access: http://altis-ism.org.ua/index.php/ALTIS/article/view/322
• Journal Title: Tooling materials science

The possibilities of increasing the efficiency of separation according to the defectiveness of the surface of diamond grinding powders in an aqueous medium are considered. The study was carried out on diamonds of grade AC20, grain size 200/160. Application of finely dispersed ferromagnetic particles with a particle size of less than 1000 nm with a concentration of these particles of 2.5 ± 0.1% to defective areas of grain surfaces was carried out in a weakly alkaline aqueous medium with constant stirring for 25 ± 2 min. After application, the water with non-fixed iron powder particles was poured off, and the diamond powder with iron particles fixed on the surface of the grains was dried and then separated in a magnetic field on a 138 T electromagnetic separator at a strength of 5 to 20 A/m to obtain four fractions. The studies performed have shown that in a weakly alkaline solution, solid metal particles interact with the formation of iron metal oxide hydrate, which are deposited on the surface of diamond grains, primarily on activated centers, which appear on diamond grains on protrusions where a maximum of dislocations accumulate. After drying, the diamond powder with solid metal particles fixed on the surface of the grains provides enhancement and creation of acquired magnetic properties for subsequent separation in a magnetic field into diamond fractions with different magnetic properties. It has been established that according to the results of the adhesion-magnetic distribution of the initial diamonds of grade AC20 with a grain size of 200/160, obtained in the Ni-Mn-C system, powders were obtained, which, according to the coefficient of surface activity Ka, differ from each other from 0.59 to 1.34%, which provides the separation from the initial diamond grinding powders of 14.8% of diamonds of AC50 of with homogeneity of diamond grinders powders of strength 1.9 times higher than the uniformity of the initial powders.