▎ 摘　　要

NOVELTY - The device has a machine seat (1) that is provided with a growing furnace (2). The growing furnace comprises a furnace tube (20) and a heating component. A substrate fixing component (3) comprises a cover plate (30) for sealing the opening. A main frame is connected with the supporting cover plate pipe (31). The main frame is provided with groups of mandrels that are capable of extending into the opening towards the opening. The end surfaces of the substrate around the reel are provided with a pressing sheet for fixing the metal substrate. The core shaft is a hollow pipe with opening ends. The air inlet is connected with the supporting air pipe. The supporting air pipe is connected with the external air source device. A driving component (4) is connected with the substrate fixing component for pushing the cover plate of the substrate fixing component to seal the opening. USE - Device for preparing graphene film with large crystal domain size used in graphene processing technology field. ADVANTAGE - The device has large crystal domain size, and ensures the film forming quality. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a device for preparing graphene film with large crystal domain size. 1Machine seat 2Growing furnace 3Substrate fixing component 4Driving component 5Air pressure monitoring sensor 20Furnace tube 30Cover plate 31Supporting cover plate pipe