Method for preparing cubic boron nitride monocrystal micro powder by using magnesium-based compound catalyst and application of cubic boron nitride monocrystal micro powder

The invention discloses a method for preparing cubic boron nitride (cBN) monocrystal micro powder by using a magnesium-based compound catalyst, which comprises the steps of: first, selecting the mixture of magnesium-based compound catalysts Mg3N2 and Mg as the compound catalyst and selecting hBN (Hexagonal Boron Nitride) powder as a raw material, respectively weighing the compound catalyst and the hBN powder and putting into a vacuum blender mixer to mix uniformly; second, taking out the uniformly mixed compound catalyst and hBN powder, pre-pressing on a press to form cylindrical synthesis bars, assembling the synthesis bars into a synthesis block and putting into a constant-temperature drying oven for heat preservation; third, putting the synthesis block in a high-pressure cavity of a six-surface diamond presser for high-temperature high-pressure synthesis experiment; and fourth, crushing the sample obtained by the high-temperature high-pressure synthesis, and carrying out impurity removal and drying to obta