A Comparative Life Cycle Assessment of HP's MultiJet Fusion Additive (3D Printing) Manufacturing with Injection Molding

HP’s MultiJet Fusion (MJF) technology, a process by which monolithic objects are created by multi-layer deposition of a fuser into a bed of resin powder through a process leveraged from HP’s inkjet printing technology, is... [ view full abstract ]

HP’s MultiJet Fusion (MJF) technology, a process by which monolithic objects are created by multi-layer deposition of a fuser into a bed of resin powder through a process leveraged from HP’s inkjet printing technology, is a new addition to the additive, or 3D, manufacturing process ecosystem. As with other additive manufacturing methods MJF has potential rapid-prototyping and customization but because of its higher speed it also has the potential to be useful for manufacturing applications often performed using injection molding.  This study seeks to understand the environmental tradeoffs between the two processes. The primary impact of low-volume injection molding comes in preparing the mold, whereas the major impacts from MJF come from energy and waste, sothe environmental crossover is quite sensitive to any factors that affect MJF-produced part.  In a direct comparison of equivalent, actual automobile parts for either process we find that the environmental crossover is on the order of a few tens to hundreds of parts.  However, when the unique benefits of additive manufacturing, such as dematerialization without compromising structural integrity or the potential for extended product life due to increased availability of replacement parts, are included the environmental crossover increases substantially.   We investigate these, as well as factors that affect energy and waste, to gain a better understanding of the potential environmental impacts and hot spots of MJF as a manufacturing process.