An adaptable FEA simulation of material extrusion additive manufacturing heat transfer in 3D

Bonding in additive manufacturing (AM) remains a key challenge in improving part properties. For thermally driven AM methods, such as material extrusion AM (MatEx), temperature governs bonding. Experimental measurements of temperature are limited in their ability to probe many points in space and time during a process without disturbing the temperature profiles being measured. These limitations may be overcome with computational methods; however, computing power considerations confined simulations to one or two dimensions until recently. Additionally, most existing models have had only limited ability to modify geometry or process parameters. In this work, an adaptable FEA model capable of simulating heat transfer in 3D and at sufficiently small time scales to capture the rapid cooling in AM is presented. Cooling trends from simulation are shown to be in agreement with experimental data. Temperature profiles are collapsed to equivalent time at a reference temperature and predict little variation in bonding along the z-axis of a part or with changes in print speed. A previously unreported peak in cooling rates for print speeds between 10 and 30 mm/s is shown. Uniformity in equivalent time at Tg suggests weld strength will not vary with print speed; however, high cooling rates for common print speeds may lead to greater residual stresses and reduced mechanical properties.