Densification Behavior and Mechanical Properties of PBX Substitute Composites Prepared by Ultrasonic Assisted Pressing of Powder

摘要

The rates of densification and density uniformity are a key performance of PBX parts. Based on ultrasonic vibration technology, this paper designs and manufactures an upper and lower 20 kHz longitudinal and radial vibration assisted molding system with a 200 mm diameter compacting part at the center axis. In this work, PBX substitute composite was successfully fabricated by pressing of powder with ultrasonic vibration and the influence of ultrasonic vibration force coupling on the mechanical properties of PBX substitute powder was investigated. Applying ultrasonic vibration to result in great rates of densification and higher efficiency of the process is expected. The effects of particle size and vibration amplitude and pressure on the densification behavior and of PBX substitute powder are discussed. The results show that applying ultrasonic vibration leads to a higher relative density and an improved homogeneity, and the growth of the size of the pressed sample can be reduced with the ultrasonic vibration and the larger of static pressure, the smaller of the pressed sample size change. In addition, ultrasonic vibration has a great effect on the finer particles.