Институт материаловедения Хабаровского научного центра Дальневосточного отделения РАН, Хабаровск, Россия.

М. И. Дворник, старший научный сотрудник, канд. техн. наук, эл. почта: Maxxxx80@mail.ru
Е. А. Михайленко, научный сотрудник, канд. физ.-мат. наук, эл почта: Mea80@list.ru

Для получения инструментального материала, обладающего высокой твердостью поверхности и трещиностойкостью основы при невысоких затратах, был проведен эксперимент по спеканию с избытком и недостатком углерода двухслойного градиентного сплава из порошков, полученных электроэрозионным диспергированием сплавов ВК8 и ВК15. Для получения исходного порошка отходы сплава ВК8 в виде пластин с исходным содержанием углерода 5,6 % диспергировали в масле, что привело к появлению избытка углерода в нем (3,1 %), который затем был частично снижен до 0,6 % путем термической обработки в атмосфере CO₂. Сплав ВК15 с исходным содержанием углерода 5,3 % диспергировали в воде для формирования недостатка концентрации углерода (2,8 %) в нем, который затем был частично снижен путем термической обработки в атмосфере CO до 0,7 %. Установлено, что диспергированный порошок состоит из сферических микрочастиц и агломерированных наночастиц, полученных кристаллизацией жидкой и паровой фаз. В результате перемешивания вольфрамовой и кобальтовой фаз произошло многократное уменьшение диаметров зерен WC во вновь спеченном сплаве. Сочетание соответствующих отклонений в содержании углерода в слоях спекаемого сплава позволило предотвратить выравнивание концентрации кобальта (8 и 15 %) и тем самым обеспечить повышенную твердость поверхности (1820 HV) и трещиностойкость основы (14,2 МПам). Были оценены затраты энергии и эффективность лабораторной установки при электроэрозионном диспергировании твердых сплавов.

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