Dr. Chen Teams Up with Argonne to Improve 3D Printing

Dr. Lianyi Chen’s team at Missouri University of Science and Technology, just completed a study with Dr. Tao Sun’s team from the U.S. Department of Energy’s Argonne National Laboratory to understand the physics behind additive manufacturing and help eliminate structural defects in 3-D printed materials.

Additive manufacturing, often referred to as 3-D printing, has the potential to transform manufacturing as engineers use titanium and other metal alloys to tap raw materials more efficiently, which in turn will reduce product costs and weight and shorten supply chains.  With this technology, possibilities seem to be endless as scientists create things such as medical prosthetics, jet engines, and even vehicles.

Yet metal additive manufacturing faces roadblocks. Printed materials often contain structural defects and vary from their designs, forcing engineers to repair their finished pieces or start over from scratch. And not all physics behind the process are well understood.

To address these problems, scientists at Missouri S&T and Argonne National Laboratory investigated the entire 3-D printing process, including the properties of the powders, how the powders are spread to form a powder bed, and how the laser fuses those powders into the desired components, to discover both how defects form and methods to avoid them.

The team showed they can observe and quantify many metal 3-D printing characteristics — including dynamics of powder spreading, melt pool size and shape, powder ejection, solidification, porosity formation and phase transformations. Ultimately, these efforts will achieve the best of both worlds: Scientists will uncover the dynamic mysteries of metal additive manufacturing, while industries will thrive with blueprints to rapidly print cost-effective and reliable products. 

Chen’s research was reported in Acta Materialia, “Transient dynamics of powder spattering in laser powder bed fusion additive manufacturing process revealed by in-situ high-speed high-energy x-ray imaging”, Qilin Guo of Missouri S & T and Cang Zhao of Argonne National Laboratory as the leading authors; and in the Scientific Reports, “Revealing particle-scale powder spreading dynamics in powder-bed- based additive manufacturing process by high-speed x-ray imaging”, Luis I Escano of Missouri S&T as the leading author. The work published in Acta Materialia is also a feature story published on the Argonne National Laboratory website. Other publications related to this research include an article in the Scientific Reports, “Real-time monitoring of laser powder bed fusion process using high-speed x-ray imaging and diffraction.”