Researchers develop abrasion-based process for producing metal powders for AM

April 13, 2022

Panel showing metal powders produced using the abrasion-based process. Left: SEM image showing distribution of powder sizes. Right: Typical single powder particle, approximately 30-50 μm in diameter (Courtesy Laboratory for Advanced Manufacturing & Finishing Processes (LAMFiP), IISc)
Panel showing metal powders produced using the abrasion-based process. Left: SEM image showing distribution of powder sizes. Right: Typical single powder particle, approximately 30-50 μm in diameter (Courtesy Laboratory for Advanced Manufacturing & Finishing Processes (LAMFiP), IISc)

A team of researchers at the Indian Institute of Science (IISc), led by Koushik Viswanathan, Assistant Professor at the Department of Mechanical Engineering, have reportedly identified an alternative technique to produce metal powders for Additive Manufacturing by using an abrasion-based process.

Metal powders used for Additive Manufacturing are predominantly produced using atomisation, a process in which a molten metal stream is broken up into fine droplets using gas or water jets. However, despite its widespread use, explains the IISc researchers, atomisation returns poor yield, is relatively expensive and limited in the types of materials. The alternative technique developed by the researchers is said to side-step these problems.

In the metal grinding industry, the material removed, known as swarf, is often discarded as a waste product. It is commonly stringy in shape, like metal chips, but can also include perfectly spherical particles. Scientists have long theorised that these particles go through a melting process, which results in the spherical shape. But this raises some interesting questions, such as whether the heat from the grinding causes the melting, or if there is actually any melting at all?

Viswanathan’s team has shown that these powder metal particles do indeed form as a result of melting due to high heat from oxidation, in an exothermic reaction at the surface layer. The team refined this process to produce large quantities of spherical powders, which are further processed to be used as stock material in Additive Manufacturing. The study is said to illustrate that these powder particles perform just as well as commercial gas atomised powders, when used in metal Additive Manufacturing.

Priti Ranjan Panda, a PhD student at IISc’s Centre for Product Design and Manufacturing and one of the authors of the study, commented, “We have an alternative, more economical and inherently scalable route for making metal powders, and the quality of the final powders appear to be very competitive when compared with conventional gas atomised powders.”

Regarding the applications of their findings, Viswanathan added, “There has been significant recent interest in adopting metal AM because, by nature, it enables significant customisation and allows design freedom. However, the large cost of stock metal powders has been the stumbling block. We hope that our work will open new doors to making cheaper and more accessible metal powders.”

Harish Singh Dhami, a PhD student at the Department of Mechanical Engineering and co-author of this study, noted, “Reducing the cost of the AM process (via economical powders) can widen the range of materials in situations such as manufacturing of biomedical implants, which could become cheaper and more accessible.”

The researchers reported that making metal powder using abrasion also has potential in other high-performance applications such as in aircraft engines, where a high degree of specification is required.

The full paper titled ‘Production of powders for metal Additive Manufacturing applications using surface grinding’, by Harish Singh Dhami, Priti Ranjan Panda, and Koushik Viswanathan, was published in Manufacturing Letters, Volume 32, 2022, ISSN 2213-8463

iisc.ac.in

In the latest issue of PM Review…

Download PDF

Extensive Powder Metallurgy industry news coverage, and the following exclusive deep-dive articles and reports:

  • From powder modification to rejuvenation: Fluidised Bed Reactors in metal powder production and Additive Manufacturing
  • Retech: Enabling the atomisation of reactive and refractory alloys at substantially higher levels of productivity and lower cost
  • Sustainability in Powder Metallurgy: Highlights from the 41st Hagen Symposium
  • Innovations from Japan’s Powder Metallurgy industry: award winners highlight novel automotive and healthcare applications

The latest news from the world of metal powders, delivered to your inbox

Don't miss any new issue of PM Review, and get the latest industry news. Sign up to our weekly newsletter.

Sign up

Join our community

Discover our magazine archive…

The free-to-access PM Review magazine archive offers unparalleled insight into the world of Powder Metallurgy from a commercial and technological perspective through:

  • Reports on visits to leading PM part manufacturers, metal powder manufacturers and industry suppliers
  • Articles on technology and application trends
  • Information on materials developments
  • Reviews of key technical presentations from the international conference circuit
  • International industry news

All past issues are available to download as free PDFs or view in your browser.

 

Browse the archive

 

Looking for PM production equipment, metal powders, R&D support and more?

Discover suppliers of these and more in our
advertisers’ index and buyer’s guide, available in the back of PM Review magazine.

  • Powders & materials
  • Powder process, classification & analysis
  • PM products
  • Atomisers & powder production technology
  • Compaction presses, tooling & ancillaries
  • Sintering equipment & ancillaries
  • Post-processing
  • Consulting & toll sintering
View online
Share via
Copy link