Finite element analysis of sintering deformation in aluminum finned heatsink printed by binder jetting.

Binder jetting (BJT), a sinter-based additive manufacturing method, has great potential to enable the mass production of metal parts because of its high productivity and low-cost printers. The ability to manufacture aluminum parts by BJT will lead to the fabrication of heat-dissipation devices whose cooling efficiency is improved through unique geometric designs. Although liquid-phase sintering is effective for densifying aluminum green parts without applying pressure, liquid decreases the apparent viscosity of the components, resulting in deformation. The ability to predict the sintering-induced deformation minimizes the costly and time-consuming trial and error required to produce parts with high accuracy. We used numerical simulations to predict the deformation in an aluminum finned heatsink, which is one of the most versatile heat-dissipation devices. The viscoplastic finite element method, in which the viscosity for liquid-phase sintering was calibrated on the basis of experiments, accurately simulated the changes in shrinkage over time during sintering. The calibrated simulator analyzed the effect of the heatsink's design on its deformation behavior, whereas thicker fin plates decreased the tilting of the fins and increased the bending of the base plate, and the number of fins hardly affected either deformation behavior. The methodology established in this work is valuable in manufacturing aluminum heatsinks with the desired shape by BJT. [ABSTRACT FROM AUTHOR]