Abstract: Photonic annealing is used to treat electrically-conductive thermoplastic. The thermoplastic forms, partially or wholly, a part which may be formed by additive manufacturing, like fused filament fabrication (FFF). The photonic annealing improves part conductivity and also alter, enhance, or give rise to other material properties while taking significantly less time than other conventional post-process methods. For instance, the baseline conductivity of the electrically-conductive thermoplastic material may be on the order of 103 S/m or lower. After the photonic annealing, its conductivity may be raised to the order of 104-105 S/m or more. This represents an improvement of 10-100× or even more of conductivity of the electrically-conductive thermoplastic compared to electrically-conductive thermoplastic prior to the photonic annealing.