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Research on the Influence of Friction Pairs on the Output Characteristics of the Piezoelectric Ultrasonic Actuator

The piezoelectric ultrasonic actuator is driven by the friction coupling between the stator and mover. Its friction pairs are very important, but there are few studies on the long-term output stability. Therefore, zirconia (ZrO2) is selected as a stator material to form friction pairs with four different wear-resistant materials: silicon nitride (Si3N4), ZrO2, bearing steel (GCr15) and polyether ether ketone (PEEK). Experiments show that the friction pair composed of ZrO2-Si3N4 is the best, and the attenuation percentage of the speed from the initial state to the end state in the speed rising stage of 50 m is 3.66%. A linear piezoelectric platform is developed based on the best friction pair; a maximum speed of 426.2 mm/s and a resolution of 85 nm are achieved.