Die Filling of Aerated Powders

Publication Reference: 
Author Last Name: 
Joesry R. El Hebieshy, Qiong Cai, Chuan-Yu (Charley) Wu
Report Type: 
Research Area: 
Powder Flow
Publication Year: 
Publication Month: 
United Kingdom

Executive Summary

Many particulate products are manufactured through powder compaction, in which die

filling is a critical process stage as the die filling performance will determine the process

efficiency and product quality. For aerated powders, the interaction between particle and

the surrounding air could play an important role during die filling. Although die filling

has attracted increasing attention over the last two decades, our understanding on die

filling of aerated powders is still limited. In particular, how the system design will affect

the die filling performance, how significant the presence of air will affect die filling

behavior, and whether powders can segregate during die filling are still not well

understood. To address these questions, both experimental and numerical investigation

were carried out on this project, and this report summarise the key findings on these three

aspects. This report contains 5 chapters: the first two chapters examine the effect of

system design (die shape, size and orientation) with experimental work reported in

Chapter 1, and numerical study in Chapter 2. The effect of air presence on die filling

behavior was presented in Chapter 3 and Chapter 4, with chapter 3 focusing on

theoretical modeling and Chapter 4 on measuring air pressure buildup in the die. Chapter

5 reports the size-induced segregation during die filling.

We would like to acknowledge IFPRI for financially supporting this project. We also

would like to thank Michele Marigo and Tim Freeman for constructive discussions

throughout this project.