Densification by ultrasonics

Abstract

High-performance densification of powder materials has long been a challenging issue in many critical applications. The presence of two weaknesses, namely not reaching a density close to 100% and the presence of porosity in parts produced by powder metallurgy, can significantly affect mechanical performance. While there are various strategies to enhance powder densification processes, ultrasonic densification presents a novel approach for producing new materials with targeted properties. Utilizing ultrasonic assistance in the densification process offers simplicity, sustainability, and reliability, along with superior mechanical and microstructural performance. In the layout of this mini-review, we first introduce and explain the basics of ultrasonication and its potential applications. We then categorize and present the underlying mechanisms, such as surface effects and volume effects, highlighting the latest developments reported in the literature related to ultrasonic densification processes. Following a comprehensive discussion of the critical input and output parameters involved in any ultrasonic densification operation, we also review and discuss the simulation efforts that have been published in this field. It is believed that ultrasonication has significant potential for application across many technologies, from medicine to energy sectors, yet numerous questions remain to be addressed to bridge existing gaps.