▎ 摘　　要

NOVELTY - Preparing graphene powder comprises (i) dispersing graphite powder in solvent, ultrasonically cleaning at 30-100 kW for 30-60 minutes to remove surface oil and impurities, then cleaning using ethanol and then freeze-drying under vacuum at 0.1 MPa at -80 degrees C for 10-30 hours to obtain pretreated graphite powder, (ii) subjecting the pretreated graphite powder to intercalation heat treatment under atmosphere protection and (iii) subjecting the graphite powder after intercalation heat treatment to high-speed vibration shear ball milling and peeling under low-temperature liquid nitrogen conditions to obtain the product. USE - The powder is useful as reinforcement material in metal composite materials, preferably titanium-based, copper-based or aluminum-based composite material (all claimed). ADVANTAGE - The method: produces graphene powder with low density defect and multi-level distribution; is environmentally friendly; realizes low device requirements; ensures high output; and is suitable for large-scale industrial production. The powder improves the performance of metal composite material.