<p>Large-scale additive material extrusion (LS-MEX) enables the fabrication of components in novel spatial and temporal dimensions. The mechanical properties of printed parts are primarily governed by the process-induced structure, which arises from the interplay between the polymer’s intrinsic material behavior and the applied process parameters. Among these, the interfaces between adjacent strands represent the weakest zones. In semi-crystalline thermoplastics and their composites, interfacial strength is dictated by molecular-chain interdiffusion, crystallization kinetics and morphology. The precise modification of the surface temperature of the substrate or freshly deposited strand, by means of integrated heating or cooling modules, results in the alteration of microscale phenomena in situ. Consequently, this process promotes targeted molecular mobility and efficient mechanical interlayer bonding. This study systematically investigates temperature‐controlled LS-MEX of polyamide 6 reinforced with 40 weight% carbon fibres (PA6 40 wt% CF). Tensile strength, elongation at break, and elastic modulus are measured by quasi-static tensile tests. Fracture surfaces are examined via confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) in order to assess interfacial adhesion, while wide-angle X-ray diffraction (WAXD) is used to evaluate crystallographic orientation. The study depict that within an optimal temperature range, the mechanical performance of LS-MEX components is enhanced. The crystalline phase remains unaltered, while a reorientation of the crystallite structures is observed. The findings of this study offer guidance for the selection of optimised process parameters, with the aim of improving layer adhesion.</p>