CURRENT STATE AND PROSPECTS OF TECHNOLOGICAL QUALITY ASSURANCE OF FDM PARTS BY MEANS OF MACHINING

Abstract

The paper considers the current state and prospects of quality assurance of parts manufactured by Fused Deposition Modeling (FDM) using machining as an effective post-processing method. The relevance of the study is driven by the transition of additive manufacturing from rapid prototyping to the production of functional mechanical components, which requires achieving high precision (IT7–IT9) and low surface roughness (Ra 0.8–1.6 μm) that FDM printing alone cannot provide. The main factors influencing the surface quality and dimensional accuracy of FDM parts are analyzed, including printing parameters, material anisotropy, and the specific mesostructure of thermoplastics.
The research methodology is based on a systematic analysis of the cutting mechanics of polymer structures, specifically PETG. A significant scientific problem identified is the occurrence of elastic recovery (elastic deflection) of the workpiece during milling.
The study proposes a comprehensive three-level compensation system to overcome these errors. The first level involves technological optimization of machining allowances (0.4–0.6 mm) to ensure the tool operates within the solid material body. The second level focuses on tool geometry stabilization, recommending mills with sharp cutting edges and high rake angles to transition the process into the pure cutting zone. The third, and most innovative level, is the algorithmic digital compensation of CNC toolpaths. This approach accounts for the variable local stiffness of the part, which depends on the internal infill patterns (grid, gyroid, honeycomb).
The results demonstrate that implementing digital trajectory correction allows for the compensation of elastic recovery, ensuring stable quality in hybrid manufacturing. The obtained results can be directly applied in the development of technological processes for manufacturing high-precision components in modern mechanical engineering, such as aerospace parts and unmanned aerial vehicle (UAV) drive systems.