While binder jetting is rapidly emerging as an ideal production-ready, high throughout AM technology, with a vast and growing range of compatible materials, until today one of the key materials used especially in the automotive industry (which is expected to be a major adopter of these technologies) was still a mirage: now that all may be changing with a new aluminum binder jetting powder developed by material technology company Equispheres.
Binder jetting can use many of the materials available for more traditional MIM (metal injection molding) processes. Aluminum, however, is not one of these as it has never really been industrialized for use in MIM (although some attempts have been made).
Now Equispheres, in partnership with McGill University, has announced the results of extensive testing which found Equispheres’ AlSi10Mg aluminum alloy powders (the same alloy used in powder bed fusion processes) suitable for sintering with binder jet technology. These findings have major implications for the automotive industry as aluminum alloys represent over 30% of the overall material demand in this space.
Specifically, the study observed compaction-free, sub-solidus sintering of Equispheres’ standard AlSi10Mg aluminum alloy powder , along with good densification (superior to 95%) and an excellent microstructure.
Aluminum binder jetting is here
Equispheres’ CEO, Kevin Nicholds is quite optimistic regarding these results. “We are excited about the industry response to our unique aluminum sintering results,” he said. “Although binder jet printer technology offers the speed and cost reductions necessary to enable additive manufacturing to meet the requirements of automotive mass production, the inability to print with aluminum alloys has been a major limitation to the technology – until now.”
Binder jet printers such as those presented by HP and Desktop Metal are potentially up to 100 times faster than traditional laser-based additive manufacturing (AM) printers and hold the promise of enabling AM to be used in mass production. However, until now, binder jet printer technology was unable to sinter aluminum alloys. The powder, developed by Equispheres, premise to enable this efficient and scalable digital production method to work with some of the most in-demand production materials.
“The unique and tailored attributes of Equispheres powder have proven exceptional in compaction free sintering,” explained Dr. Mathieu Brochu, Associate Professor at McGill and Canada Research Chair in Pulse Processing of Nanostructured Materials, “We are excited to begin work with Equispheres’ binder jet printing partners in the next phase to fully understand all aspects related to sintering of complex shape components and the fundamental relations with new specialized binder agents.”
Equispheres is presently working with key partners on the development of specialized binder agents required for aluminum and for specific automotive applications. The company expects that the process and powder will become a standard for many critical parts as the process is refined and testing continues.