Method for preparing silicon carbide powder material by utilizing waste circuit substrate

The invention provides a method for preparing a silicon carbide powder material by utilizing a waste circuit substrate. The method comprises the following steps: crushing the waste circuit substrate,sorting out copper powder, crushing the remaining substrate, performing acid pickling, and performing drying; under protection of an inert gas, performing pyrolysis at the temperature of 200-900 DEG Cfor 0.1-3 h, and performing cooling to room temperature to obtain a pyrolysis product; putting the above pyrolysis product into a graphite furnace, under protection of an inert gas, performing carbonthermal reduction at the temperature of 1000-2000 DEG C for 0.1-10 h, performing cooling, and performing grinding to obtain a carbon thermal reduction product; and performing acid pickling on the above carbon thermal reduction product, performing washing by using water until the solution is neutral, performing drying, and performing grinding to obtain the silicon carbide powder material. The method provided by the inventio