Singapore University of Technology and Design: Particle Reinforced Metal Nanocomposites for SLM

In ‘Particle-reinforced metal matrix nanocomposites fabricated by selective laser melting: A state of the art review,’ researchers, including a team from Singapore University of Technology and Design, bring together a more complex study of composites; in this case, they are delving into a new study regarding particle reinforced metal matrix nanocomposites (MMNCs) for use in metal 3D printing and additive manufacturing processes like selective laser melting.

Helpful in applications like the automotive industry, biomedical, aerospace, and numerous military divisions, MMNCs are becoming more attractive for use not only due to so many of the classic 3D printing and AM benefits but also their ability to offer the following:

• High strength
• Thermal stability
• Ductility
• Isotropy

SLM is used both with metal and ceramics and the researchers point out that it shows ‘promising potential’ for creating complex structures with suitable mechanical properties like MMNCs—although high energy consumption is still necessary for attaining the proper levels of microstructural strength and stability.

“MMNCs have always been a huge interest for material scientists. With the advancement in advanced manufacturing, particularly additive manufacturing, there is now greater potential in achieving high quality MMNCs. In our review, laser powder bed fusion is chosen as the process in focus as it has proven its capabilities in fabricating functional parts from metals and ceramics,” explained principal investigator and co-author Professor Chua Chee Kai from SUTD.

AM processes, employing a high-power laser system, also allow for faster turnaround and incredible opportunity for customization—which often means that parts that may not have been possible before can now be created quickly and affordably.

Schematic of nanoparticle distribution in TiC/Ti nanocomposite powders produced by ball milling and direct mixing, prepared for SLM.

“One of the key challenges in AM is the lack of ‘printable’ materials. We believe this comprehensive review provides a timely overview and understanding of SLM for MMNCs by focusing on the merits while not ignoring the limitations. This hopefully will encourage more researchers to explore this highly interesting area,” said co-author Dr Sing Swee Leong from Nanyang Technological University.

The review also offers a central focus on feedstock preparation, along with comparing techniques in detail. The researchers also detail suitable mechanical properties for nanocomposites, to include enhancing mechanisms, strength, microhardness, and fatigue. The authors also delve into defects associated with SLM, categorizing them by classification, mechanisms of formation, and tendency in MMNCs.

As 3D printing and additive manufacturing processes continue to expand around the world, along with a wide range of new hardware, software, and materials that are becoming vastly accessible and affordable, composites are becoming sought-after as well as created by many different researchers, engineers, and users on every level. Metal composites are popular such as copper metal PLA, continuous wire polymers, wood, and more. What do you think of this news? Let us know your thoughts! Join the discussion of this and other 3D printing topics at 3DPrintBoard.com.