Metals-based additive manufacturing (AM) encompasses several different technologies that enable the controlled fusing, melting, and consolidation of precursor metal materials into metal 3D parts and structures, enabling complex geometry and material designs.  The fundamental physics of these processes is relatively complex, involving various engineering disciplines such as fluid mechanics, heat transfer, dynamics and system controls, optics, metrology, and data science.   Measuring the various dynamic physical phenomena during the fabrication process can enable users to observe and track the quality of the fabrication, and thus the quality of the part as it's being built, through in-process monitoring (IPM).  Various methods of IPM have been tested in the research community which include highly novel methods such as melt pool emission thermography or spectroscopy, structured light projection or other machine vision applications, acoustic emission, and other sensing modalities.  Several of these technologies are now provided as commercial instruments on industrial metal AM machines.

The goal of this research opportunity is to explore and advance the various existing commercial and research technologies that are currently (or have future potential to be) employed for IPM of industrial metal AM machines, and developing new methods for their integration into machine, process, or part qualification.

NIST has researched various aspects of in-process monitoring (IPM) of metal AM systems for over 10 years, and potential applicants can utilize and build upon NIST's repertoire of instruments, facilities, ongoing research, and interdisciplinary network of scientists and engineers involved in this subject.  Applicants may tailor their proposals to make use of the following ongoing research and facilities at NIST: 

•  Develop methods for calibration and characterization of commercial IPM instruments,
• Develop instrument models relating physical measurands to instrument signals
• Innovate new in-line signal processing, measurement data analysis algorithms, and data visualization techniques. Innovate and test new instrument types and measurement methods, 
• Work with commercial and custom-made measurement instruments, such as fringe projection, high speed imaging and thermography, radiometry and emission spectroscopy
• Work with multiple metal AM systems available at NIST, including single-laser and multi-laser powder bed fusion (L-PBF), hybrid 5-axis machining and laser-wire direct energy deposition (L-DED), and metal binder jetting (BJ)