Abstract: The effects of vibration parameters on particle screening efficiency were studied by using dried silicon powder， molybdenum powder and zinc powder as typical materials. Firstly， the effects of vibration frequency， angle of eccentric block， thickness of material layer and different material properties on the screening efficiency of common rotary vibrating screen were investigated， and the optimal vibration parameters of typical materials under the action of common rotary vibrating screen were obtained. Then， the ultrasonic vibration experiment was carried out. The experiment shows that the ultrasonic vibration could effectively disperse the particle aggregates of the fine powder materials， solve the problem of the screen hole blockage， thus improving the screening efficiency significantly. According to the experimental results， the optimum combination parameters of silicon powder particles under the combined action of ordinary vibration and ultrasonic vibration can be obtained.

Key words: screening efficiency, vibration frequency, optimal vibration parameters, ultrasonic vibration