Metrology for additive manufacturing (3D printing) technologies

The findings presented in this paper stem from the survey of unclassified literature on additive manufacturing (AM)/3D printing technologies and their metrology (science of measurements). AM technologies allow engineers to design and build parts more freely than ever before. They also help to make production more distributed and eliminate obsolescence. This paper introduces different types of AM, as well as metrology challenges that NSWC Corona, the leading agency for the US Navy's Metrology and Calibration (METCAL) program, needs to address. It discusses potential uses, process limitations and metrology related to three popular categories of AM technologies; material extrusion (e.g., fused deposition modelling), powder bed fusion (e.g., selective laser melting) and directed energy deposition (e.g., laser-engineered net shaping). Powder bed fusion and directed energy deposition have proved capable of firearm and aerospace-grade manufacturing. AM technologies demonstrate huge promise and may revolutionise design, manufacturing, logistics, maintenance and acquisition in the Navy. However, there are still multiple hurdles to overcome before AM becomes an effective component in the military toolset. As AM continues to advance, the only way to ensure these new technologies fit as reliable pieces of the warfighter arsenal is to prioritise the development of corresponding measurement techniques and calibration schedules.