Method for printing three-dimensional parts with cyrstallization kinetics control

A method for printing a three-dimensional part from with an additive manufacturing system, the method comprising:

• providing a part material that compositionally comprises one or more semi-crystalline polyaryletherketone polymers and one or more amorphous polymers that are substantially miscible with the one or more semi-crystalline polymers;
• maintaining a build environment of the additive manufacturing system, at least in a deposition region of the build environment, at a temperature that is below a cold crystallization temperature of the part material;
• feeding the part material as a continuous filament feedstock to a print head retained by the additive manufacturing system;
• melting the part material in the print head;
• extruding the melted part material from the print head;
• and
• depositing the extruded part material in the deposition region in a layer-by-layer manner to form at least a portion of a layer of the three-dimensional part from the extruded part material, wherein a temperature of the portion of the layer is cooled to a temperature below the cold crystallization temperature while the amorphous polymer retards crystallization of the one or more semi-crystalline polyaryletherketone polymers, such that residual stresses in the portion of the layer are managed to substantially prevent curling.