▎ 摘　　要

NOVELTY - Ultrasonic motor rotor friction material comprises polymer-based complex material comprising 100 pts. wt. polyimide, 1-5 pts. wt. rare earth oxide, 1-5 pts. wt. graphene oxide, and 1-5 pts. wt. multi-wall carbon nanotubes. USE - Used as ultrasonic motor rotor friction material. ADVANTAGE - The method: is simple, convenient, suitable for industrial mass preparation and economical; avoids problems that the traditional friction material sticks to the surface of the aluminum alloy rotor and falls off and has short life. The complex material has light weight, stable friction coefficient and ultra-low wear rate, is easily processed into a rotor and used in a rotary ultrasonic motor; reduces the weight and service life of the ultrasonic motor. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) manufacturing the ultrasonic motor rotor friction material comprising (i) dispersing graphene oxide, multi-walled carbon nanotubes and rare earth oxides in absolute ethanol, ultrasonic dispersion plus mechanical stirring for 2-6 hours, adding polyimide to continue dispersion for 1-2 hours, completely mixing, homogenizing, drying, crushing and sieving treatment to obtain molding materials, (ii) pouring the molding material obtained in the step (i) into a mold for hot-press sintering molding, and releasing it by natural cooling to obtain polyimide nanocomposite material, and (iii) processing polyimide nanocomposite material produced into a rotor for an ultrasonic motor, polishing the surface, and using the power supply machine; and (2) ultrasonic motor rotor prepared by the above mentioned method.