Water atomisation of metal powders: effect of water spray configuration

ABSTRACT

We consider the effect of water spray configuration on the fineness and uniformity of a metal powder produced by water atomization of a melt stream. The effects of water spray travel distance, nozzle design, water pressure, melt superheat, and apex angle on the particle size distribution of a metal powder is studied via a laboratory-scale water atomizer; the main focus is on the first two, which are usually fixed parameters of the atomizer. Correlations are proposed relating the mass median size and standard deviation of the powder to the parameters cited. Similar correlations for water pressure, melt superheat, and apex angle have been reported elsewhere; we present data on these effects to confirm the validity of our results, especially as Bi-42%Sn powder has not been studied before. What is new are results on the effect of water spray travel distance and nozzle design on the mass median size and standard deviation of powder.

KEYWORDS:

• Water atomization
• parametric study
• water spray configuration
• metal powder
• powder size distribution
• flexible atomizer

Acknowledgements

The authors acknowledge the funding and support provided by Rio Tinto Metal Powders, the Natural Sciences and Engineering Research Council of Canada (NSERC), and the University of Toronto Dean’s Catalyst Professorship. Thanks to Dr. Donghui Li, Dave McDowell, Eric Wu, Ziwei Yang, Gloria Vytas, and Anagha Acharya for their assistance during the design and the construction of the water atomizer, and to John Forster for his cooperation during sieve analysis. We are also grateful to Atomizing System Limited for providing the digital template of the log-normal plot.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes on contributors

Ali Asgarian is a post-doctoral fellow in Process Metallurgy Research Lab at the University of Toronto. His research focuses on enhancement of powder metallurgy (powder production) and metal additive manufacturing through experimentation and computational simulation. He received his PhD from the University of Toronto, where he conducted research at the interface of materials science and mechanical engineering, and in collaboration with Rio Tinto Metal Powders. Dr. Asgarian is an active licensed professional engineer in Ontario, Canada with more than 10 years of experience spanning across a range of industries including metallurgical plants, process plants, and power plants. He worked for a number of well-known consulting engineering firms including Hatch Ltd.

Ziqi Tang is a recent MEng graduate from the department of materials science and engineering at the University of Toronto. Ziqi has been working as a research assistant in the Process Metallurgy Research Lab for one year. He specializes in material characterization, powder metallurgy, and data analysis.

Markus Bussmann is a Professor and Chair of the Department of Mechanical & Industrial Engineering at the University of Toronto. For many years he has been involved with modelling the flow, heat transfer and phase change associated with various industrial and materials processes including aspects of kraft chemical recovery, the melting and dissolution of metals and alloys, oil sands processing, and various spray and atomization processes.

Kinnor Chattopadhyay is an Associate Professor and Dean's Catalyst Professor at the Department of Materials Science & Engineering at the University of Toronto. He is an AIST Foundation Steel Professor and the President of Canadian Association of Recycling of Lithium Ion Batteries – CARLIB. For many years he has been involved in improving process metallurgy, especially iron and steel processing, powder metallurgy, and AI/Machine learning in metals.

Additional information

Funding

This work was supported by Rio Tinto Metal Powders; University of Toronto Dean’s Catalyst Professorship; Natural Sciences and Engineering Research Council of Canada (NSERC).